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rapaljer answered: 3620 problems
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27m^8-90m^6+45m^4 1 solutions
Answer 176700 by rapaljer(3620) on 2009-11-21 00:39:45 (Show Source):
You can put this solution on YOUR website!27m^8-90m^6+45m^4
The first step in ANY factoring problem is to take out the COMMON FACTOR. In this case, it would be 9m^4:
9m^4(3m^4 -10m^2 + 5)
The resulting trinomial does not seem to factor
I have a LOT of resources on my own website on the topic of FACTORING. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 2" for various sections on factoring, especially "Section 2.03, Factoring the Common Factor." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Basic Algebra", and look for "FACTORING."
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Trigonometry-basics/241231: PLEASE HELP ME SOLVE TIS CIRCULAR FUNCTIONS AND THEIR GRAPH:
What is the period of y=4 sin 3 x?
HERE ARE THE POSSIBLE ANSWERS:
a)pi/3
b)2pi/3
c)3pi 1 solutions
Answer 176698 by rapaljer(3620) on 2009-11-21 00:33:23 (Show Source):
You can put this solution on YOUR website!The period of y=sin x is normally 2pi. Therefore, y=sin3x is 2pi/3. Of course the 4 is the amplitude, which is irrelevant to the period.
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Sequences-and-series/241243: a) Find the sum of this sequence: 1+3+9+27..3^19
b) Form the formula by filling in the blank:
S= a + ar + ar^2 + ar^3 + ... + ar^(n-1)(The series stops at n-1 power because there are n terms, but the first one is not multiplied by r)
rS=______________?
rS=___________?(Substritute S-a)
rS-S=______?
but rS-S can be factored: rS-S=S(r-1),so
S=__________?
I got a), it is 1,743,392,200 But i have no idea how to come up with the formula, even though the book reads the general formula is S=a(r^n-1)/(r-1)
Please explain. I'm very thankful for your helps!
1 solutions
Answer 176696 by rapaljer(3620) on 2009-11-21 00:24:06 (Show Source):
You can put this solution on YOUR website!S= a + ar + ar^2 + ar^3 + ... + ar^(n-1)(The series stops at n-1 power because there are n terms, but the first one is not multiplied by r)
rS=ar +ar^2 + ar^3 + . . . + ar^n
Subtract the above equations. All the middle terms subtract out!
S-rS = a - ar^n
Factor out the S on the left and the a on the right side of the equation:
S(1-r) = a(1-r^n)
Divide both sides by (1-r):
This does not agree exactly with your final answer, so multiply both numerator and denominator by -1, and it will give you the final result you are looking for!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
real-numbers/241267: when I worked on to problems using the elimination method I came up with 0=0 in both equations. Is this a solution or non solution or infinite solution 1 solutions
Answer 176694 by rapaljer(3620) on 2009-11-21 00:12:33 (Show Source):
You can put this solution on YOUR website!When you get 0=0, this means that the statement is ALWAYS TRUE, so the lines are actually the SAME LINE. There are infinitely many solutions.
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Linear-equations/241280: I don't understand how to find slope from a graph. like i have this worksheet to do an i was absent so my teacher just gave me the worksheet, yeah i know bad teacher. anyways i'm suppose to find the slope of each line and i don't know what to do. 1 solutions
Answer 176693 by rapaljer(3620) on 2009-11-21 00:09:03 (Show Source):
You can put this solution on YOUR website!I have a LOT of resources on my own website on the topic of GRAPHING and SLOPE of a LINE. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 4" for "Section 4.02, Slope Intercept Method." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Basic Algebra", and look for "Graphing and Slope of a Line."
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
|
Polynomials-and-rational-expressions/241270: a^4 - ab^3 =
I am not sure how you solve this polynomial? Can someone explain the steps on how to work this problem?
Thanks. 1 solutions
Answer 176692 by rapaljer(3620) on 2009-11-21 00:03:44 (Show Source):
You can put this solution on YOUR website!This is a FACTORING problem. The first step in any factoring problem is to take out the COMMON FACTOR. In this case, the common factor is a
a^4-ab^3
a(a^3-b^3)
This is a DIFFERENCE of CUBES, which requires a special formula that is actually the product of a BINOMIAL times a TRINOMIAL.
a(______)(_________)
The binomial is the first, which is "a" minus the second, which is "b":
a(a-b)(___________)
The trinomial consists of the square of the first, PLUS the product of the first times the second, plus the square of the second.
a(a-b)(a^2+ab+b^2)
I have a LOT of resources on my own website on the topic of FACTORING. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Intermediate Algebra", and look in "Chapter 2" for "Section 2.01, Factoring." Select the Section called "Sum and Difference of Cubes." It's a topic that you probably will need more help with than other topics. This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Intermediate Algebra", and look for "Factoring". You don't have to watch the whole video, which is over an hour long, but instead you can fast forward the video so you can see the topic that you need help with.
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Polynomials-and-rational-expressions/241272: Perform the indicated operation.Write each answer in lowest terms.
m^2 - 1/(m - 1)^2 * 2m - 2/3m + 3 =
I am having problems understanding how to perform the indicated operation. Can someone explain to me the steps I am supposed to use and how to solve this problem? 1 solutions
Answer 176691 by rapaljer(3620) on 2009-11-20 23:48:07 (Show Source):
You can put this solution on YOUR website!Do you mean this?
If this is it, then factor everything that you can:
Divide out the (m+1) factors and all the (m-1) factors, and what is left over is  .
I have a chapter on fractions on my own website. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 3" for "Section 3.02, Multiplying and Dividing Fractions." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Equations/241275: (x-1/x)=5 find the value of x2+1/x2=? here i wrote x square not x 2 please note that.Thanks 1 solutions
Answer 176690 by rapaljer(3620) on 2009-11-20 23:39:40 (Show Source):
You can put this solution on YOUR website!If (x-1/x)=5, then square both sides and get this:
Add +2 to each side:
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Equations/241030: Factor each polynomial completely.
a^4 - ab^3 =
This is what I tried and I am not sure it is correct?
a^2a^2/a^2b^1 = a^2/b^1 I don't think this is the correct formula but I am not sure. Any help would be really appreciated. 1 solutions
Answer 176535 by rapaljer(3620) on 2009-11-20 01:09:54 (Show Source):
You can put this solution on YOUR website!The first step in factoring is to try to take out any common factors. In this case, you have a common factor of a, so take out the "a" factor.
a^4-ab^3
a(a^3 -b^3)
Now, this is a DIFFERENCE OF CUBES. There is a special formula for this in the form of a BINOMIAL times a TRINOMIAL. You may want to see my website for additional explanation of this formula. See the note at the end of this problem.
a(___)(_________)
a(a-b)(________)
a(a-b)(a^2+ab+b^2)
To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "MATH IN LIVING COLOR". Choose "Intermediate Algebra", and look in "Chapter 2" for "Section 2.01, Factoring." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Intermediate Algebra", and look for "Factoring."
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Square-cubic-other-roots/241032: Rationalize the denominator and simplify.
sqrt(6)/4sqrt(3) + sqrt(2)
I am having a real hard time figuring the square root problems.
I will try: sqrt(6)/4sqrt(3) + sqrt(2) =
sqrt(6)/sqrt(12) + sqrt(8) = sqrt(6)/sqrt(20) =
sqrt(3)/sqrt(10) answer
I am not sure I am doing this problem correctly?
Any help would be really appreciated.
1 solutions
Answer 176533 by rapaljer(3620) on 2009-11-20 00:58:26 (Show Source):
You can put this solution on YOUR website!This is a problem called "Rationalizing a BINOMIAL Denominator!" To rationalize a denominator means to "get rid of the radicals in the denominator." In the case of a binomial denominator, it takes a special trick to do what needs to be done here. You have to multiply the numerator and denominator by what is called the "CONJUGATE" of the denominator. That is, the SAME as the denominator, but with the OPPOSITE sign in the middle!! We do this for one reason--because it WORKS!! In this case, you have to multiply the numerator and denominator by  . It looks like this:
 *
Now, multiply the numerator and denominator out. Notice that the denominator is left with NO RADICALS!
In the denominator, notice that the middle terms subtract out, and the other denominator terms are PERFECT SQUARES! Simplify the numberator!
Factor the numerator so you can reduce the fraction:
FINAL ANSWER
I have a LOT of resources on my own website on the topic of SQUARE ROOTS. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "MATH IN LIVING COLOR." For problems like this one, please see "Intermediate Algebra" and look in "Chapter 3" for "Section 3.04 Rationalizing Denominators." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Intermediate Algebra", and look for "Radicals and Fractional Exponents".
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Graphs/241031: Use the rule y = -x + 7 to fill in the blank.
If (1, y) is on the graph, then y = 1 solutions
Answer 176532 by rapaljer(3620) on 2009-11-20 00:32:19 (Show Source):
You can put this solution on YOUR website!This is a LOT easier than it looks! All you have to do is realize that (1,y) means that x=1, and you have to find the value of y!
If y=-x +7, just plug in the value of x=1, and find y:
y=-1+7
y=6
That's it! FINAL ANSWER!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Quadratic_Equations/241028: Solve the following equation using quadratic formula:
x^2+12+35=0
The solution set is { , }
x=(-12±√(〖12〗^2+35))/2
(x+5)(x+7)= 12/2= {5,7}
thanks for you help
Vicki 1 solutions
Answer 176531 by rapaljer(3620) on 2009-11-20 00:29:42 (Show Source):
You can put this solution on YOUR website!The quadratic formula is
In this case, x^2 +12x+35=0, a=1, b=12, and c=35.
 or
 or
This problem can be checked by solving by FACTORING:
x^2 +12x+35=0
(x+5)(x+7)=0
x=-5 or x=-7
I have a LOT of resources on my own website on the topic of QUADRATIC FORMULA. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Intermediate Algebra", and look in "Chapter 4" for "Section 4.03, Quadratic Formula." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Radicals/241022: How do I add sqrt486 plus 2sqrt384?
The answer I have was 531,108
For sqrt49 +sqrt 9 I got an answer of 2,482, but I am not sure if this is right either.
I understand this when there is an exponent with it but I am not sure about these.
1 solutions
Answer 176530 by rapaljer(3620) on 2009-11-20 00:15:46 (Show Source):
You can put this solution on YOUR website!No, I'm afraid you missed this concept!
The second question is easiest, so let's do it first.
You have to do the square roots first, and THEN you add the results together, but ONLY IF YOU HAVE LIKE TERMS or LIKE RADICALS!!
 FINAL ANSWER for the second part of your question!
Now, the FIRST part of your question is much harder!! In fact, I don't know how they could have made this problem any harder for you! (If you don't understand my explanation here, PLEASE see the note at the end of this problem telling you about my website which has some MUCH EASIER problems to help you get started on this concept!!)
The first step is to SIMPLIFY each square root SEPARATELY! You have to try to find a perfect square that is a factor of 486. It just so happens that the PERFECT SQUARE 81 divides evenly into 486. It goes 6 times, so you can write
486=81*6.
Now do the same thing for 384. Find a perfect square that goes evenly into 384. I can't think of a perfect square that goes into this, but the previous part, square root of 486, came out with a leftover factor of 6. Do you think maybe 6 goes into 384? Indeed it does. It goes 64 times, which just happens to be a perfect square!! You can write
384=64*6
(I told you this was a HARD ONE!!)
NOW,
Now, DO the square roots that you know how to do, and leave the other ones alone!
Now, notice that you have both square roots EXACTLY the same!! This means that you can COMBINE LIKE TERMS! Add the 9 + 16, and you get 25!
I warned you that this was a HARD problem!! You probably need to see my own website in order to get some EASIER problems before you can really understand this one! I have a LOT of resources on my own website on the topic of SQUARE ROOTS. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 5" for "Section 5.01, Square Roots" and "Section 5.03 Combining Like Radicals." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Basic Algebra", and look for "Radicals (Square Roots)".
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Square-cubic-other-roots/241015: square root of 18x^4y^8 1 solutions
Answer 176528 by rapaljer(3620) on 2009-11-19 23:54:03 (Show Source):
You can put this solution on YOUR website!The first step in simplifying a square root is to SORT it into TWO square roots where the first square root contains only perfect squares, and the second square root has all the "left-over" factors. Remember also that if you have a variable raised to a power, if the power is EVEN, like x^4 or y^8, then this IS a perfect square, and to take the square root, you take HALF of the exponent.
Okay? Here we go:
Now, take the square root of the first one, since it IS a perfect square. Remember, to take HALF of the exponents! However, the second square root is NOT a perfect square, so just leave it like it is!
I have a LOT of resources on my own website on the topic of SQUARE ROOTS. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 5" for "Section 5.01, Square Roots." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
In addition, I have a video of me teaching this topic in the classroom a few years ago. To see this FREE video, from my Homepage, look for "Rapalje Videos in Living Color". Select "Basic Algebra", and look for "Radicals (Square Roots)".
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Polynomials-and-rational-expressions/240841: Solve by factoring: 5x^2=10x
1 solutions
Answer 176425 by rapaljer(3620) on 2009-11-19 16:56:28 (Show Source):
You can put this solution on YOUR website!First, you must set this equation equal to zero!
5x^2-10x =0
Now factor the left side. There is a common factor of 5x:
5x(x-2)=0
There are two solutions.
5x= 0
x=0
OR x-2=0
x=2
I have a LOT of resources on my own website on the topics of FACTORING and SOLVING QUADRATIC EQUATIONS. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 2 for the appropriate sections. This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Rate-of-work-word-problems/240843: It takes 6 hours to fill a pool. It takes 8 hours to drain it. How long does it take to fill the pool if the drain is left opened when the pool is started to be filled? 1 solutions
Answer 176423 by rapaljer(3620) on 2009-11-19 16:51:39 (Show Source):
You can put this solution on YOUR website!Let x = number of hours to fill the pool with both draining and filling.
1/6 = the part of the pool that can be filled in 1 hour
1/8= the part of the pool that can be drained in 1 hour
1/x= the part of the pool that is filled with both pipes open
1/6-1/8=1/x
Multiply both sides of the equation by 24x:
 hours
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Graphs/240786: Find the slope and y intercept of each equation. Then graph.
y=x+2
y=4/5x+2
y=7/4x+2 1 solutions
Answer 176386 by rapaljer(3620) on 2009-11-19 15:10:06 (Show Source):
You can put this solution on YOUR website!When the equation is in slope-intercept form, y=mx+b, the slope is always the coefficient of x, and the y-intercept is always the number term.
y=x+2
Slope = 1, y-intercept = 2.
y=4/5x+2
Slope = 4/5, y-int = 2
y=7/4x+2
Slope = 7/4, y-int = 2
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Linear-equations/240761: put the equation 5x-7y=9 into slope intercept form 1 solutions
Answer 176384 by rapaljer(3620) on 2009-11-19 15:05:51 (Show Source):
You can put this solution on YOUR website!To put this in slope intercept form, you have to solve for y. Start by subtracting 5x from each side.
5x-7y=9
-7y=-5x+9
Now divide by -7:
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
|
Rectangles/240741: If the dimensions of the larger rectangle are 9 by 18, what are the dimensions of the smaller rectangle? 1 solutions
Answer 176360 by rapaljer(3620) on 2009-11-19 12:47:18 (Show Source):
You can put this solution on YOUR website!Is there a diagram or picture that we are not seeing here?
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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Coordinate-system/240697: Solve x2 - 2x - 8 = 0 by graphing. The x intercepts are ? and ?. 1 solutions
Answer 176354 by rapaljer(3620) on 2009-11-19 11:36:56 (Show Source):
You can put this solution on YOUR website!Graph y=x^2 -2x-8 with a calculator.
As you can see, the x-intercepts are at x=-2 and x=4.
This can also be determined algebraically by letting y=0 and solving
0=x^2-2x-8
0=(x-4)(x+2)
x=4 or x=-2
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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Evaluation_Word_Problems/240691: Jane went fishing and caught a whopper of a fish! The head of her fish was ten inches long. The length of the fish's tail was equal to the length of the head plus half the length of the body. The body was as long as the head and tail together. What is the total length of her fish?
1 solutions
Answer 176325 by rapaljer(3620) on 2009-11-19 09:50:42 (Show Source):
You can put this solution on YOUR website!Let x = length of the body, since that is at the end of the sentence.
Now, the tail = length of the head plus half the length of the body.
tail = 10 + 1/2*x
The equation is that the body = head + tail
x= 10 + 10+ 1/2x
Subtract 1/2x from each side:
1/2x= 20
Multiply both sides by 2:
x=40 inches = Body
Tail = 10 + 1/2x
Tail = 10 + 20 = 30 inches
Total fish = Head + Body + Tail
Total fish = 10+40+30 = 80 inches! (BIG FISH!!)
Check:
Body = Head + Tail
40=10+30
It checks!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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logarithm/240559: Solve: 2log(base4)x+log(base4)3=log(base4)x-log(base4)2
1 solutions
Answer 176294 by rapaljer(3620) on 2009-11-19 02:29:10 (Show Source):
You can put this solution on YOUR website!
Multiply both sides by 2:
Factor the x:

There are two solutions:
x=0 NOTE: THIS ANSWER MUST BE REJECTED, SINCE log(0) is UNDEFINED!!
6x-1=0
6x=1
x=1/6 This one seems to work!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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Quadratic_Equations/240648: How do you find the turning point (vertex) of a Quadratic function, not using complete the square? 1 solutions
Answer 176293 by rapaljer(3620) on 2009-11-19 02:10:37 (Show Source):
You can put this solution on YOUR website!If the equation is y=ax^2 +bx +c, then the vertex is always at the value where x=-b/(2a). After you find x, substitute this back into the original equation (or let the calcluator do it for you!!) to find y.
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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Numbers_Word_Problems/240645: One number is 4 more than twice the second number. Their total is 25. Find the numbers. I just need help on writing the problem, then I will be able to solve it. 1 solutions
Answer 176292 by rapaljer(3620) on 2009-11-19 02:08:30 (Show Source):
You can put this solution on YOUR website!Let x= the 2nd number. (I always like to let x = the quantity at the end of the sentence or phrase!)
Now, the first number is 4 more than twice the second number, where the second number is x.
Therefore, first number = 2x+4.
Now the equation is that the total (or sum!) of the numbers is 25.
x+2x+4=25
You said that you can solve it, so go for it!
I have a LOT of resources on my own website on the topic of WORD PROBLEMS. To find my website, do a "BING" or a "GOOGLE" search for my last name "Rapalje". Near the top of the search list, you should see "Rapalje Homepage." Click on this, and look near the top of my homepage for the link "Basic, Intermediate and College Algebra: One Step at a Time." Choose "Basic Algebra", and look in "Chapter 1" for "Sections 1.09 and 1.10, Word Problems." This is my own explanation especially written for students who have trouble understanding math. I wrote this to students, NOT mathematicians, and I think you will find it easier to understand than your own traditional textbooks!! In addition to this page, the entire website is supported by my "MATH IN LIVING COLOR" pages, where the hardest problems are solved IN COLOR.
If you like my website, please recommend it to family and friends who have trouble understanding math!! It's ALL FREE!!!
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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Rectangles/240569: if thw area of the rectangle is 30 square inches what is the perimeter and value? 1 solutions
Answer 176291 by rapaljer(3620) on 2009-11-19 01:37:59 (Show Source):
You can put this solution on YOUR website!Not enough information is given to solve this one. The area could be 30 square inches because it is 5 by 6 or it could be 3 by 10, or many different possiblities.
Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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