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Earlsdon answered: 6285 problems
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Expressions-with-variables/152578: Please help me solve this problem: What is 7 times the sum of M and 6?
1 solutions

Answer 112154 by Earlsdon(6291) About Me  on 2008-08-19 21:13:51 (Show Source):
You can put this solution on YOUR website!
7 times the sum of M and 6 is expressed by: 7(M+6) and if you expand this, it becomes: 7M+42


Surface-area/152571: How many 1/2 inch square tiles to cover a ball 9 inches in diameter?
Thanks I can't find my formula book and I am 79 years old. (retired aerospace engineer)
1 solutions

Answer 112153 by Earlsdon(6291) About Me  on 2008-08-19 21:10:37 (Show Source):
You can put this solution on YOUR website!
The surface area of a sphere with diameter D is given by: S+=+pi%2AD%5E2


Expressions-with-variables/152595: the number of gallons in q quarts
1 solutions

Answer 112151 by Earlsdon(6291) About Me  on 2008-08-19 20:53:24 (Show Source):
You can put this solution on YOUR website!
Since there are 4 qts in 1 gallon, you would divide the number of quarts (q) by 4 to find the number of gallons, so...
g+=+q%2F4


Linear_Equations_And_Systems_Word_Problems/152592: Yesterday there were 5 times as many girls as boys in Miss Miriam's preschool. Today 4 more boys joined the preschool. Now there are 3 times as many girls as boys. How many children are now attending the preschool?
So far I know that if you let "b" equal boys and "g" equal girls the first equation is 5b=g. I also know that I am looking for "x" the total amount of children in the school or b+g=x. I am not sure where the 4 additional boys come in or how to make the equations equal so that I can solve them. I really would appreciate your help!
1 solutions

Answer 112150 by Earlsdon(6291) About Me  on 2008-08-19 20:49:20 (Show Source):
You can put this solution on YOUR website!
Ok, you got a good start!
Let b = number of boys yesterday and (b+4) = the number of boys today and g = number of girls (This didn't change).
Yesterday: g = 5b
Today: g = 3(b+4)
Since g = g, then;
5b = 3(b+4) Apply the distributive property on the right side.
5b = 3b+12 Subtract 3b from both sides.
2b = 12 Divide both sides by 2.
b = 6
So, yesterday, there were 6 boys plus 5*(6) girls for a total of 36 children.
Today, there are 6+4 = 10 boys and 3*10 = 30 girls for a total 40 children.


Polynomials-and-rational-expressions/152518: g(2+h)=x to the third
the instructor gave us x=(2+h)
and the answer 8+12h+6h suared+h to the third
i haven't been able to get that as my answer.
here's what I have done:
g(2+h)=x to the third
g=(2+h)to the third
g=(2+h)(2+h)(2+h)
g=4+2h+2h+hsquared(2+h)
g=8+4h+4h+2h+2h+2hsquared+h to the third
g=8+12h+2hsquared+h to the third
1 solutions

Answer 112094 by Earlsdon(6291) About Me  on 2008-08-19 14:03:25 (Show Source):
You can put this solution on YOUR website!
%282%2Bh%29%5E3+=+%282%2Bh%29%282%2Bh%29%282%2Bh%29 You are ok up to this point.
%282%2Bh%29%282%2Bh%29+=+4%2B2h%2B2h%2Bh%5E2 which simplifies to 4%2B4h%2Bh%5E2 Now you multiply this by %282%2Bh%29
%284%2B4h%2Bh%5E2%29%282%2Bh%29+=+8%2B8h%2B2h%5E2%2B4h%2B4h%5E2%2Bh%5E3 Combining like-terms, you get:
8%2B12h%2B6h%5E2%2Bh%5E3 So...
g%282%2Bh%29+=+8%2B12h%2B6h%5E2%2Bh%5E3


Geometry_Word_Problems/152487: Hi,
How would I solve the following: Applications of Linear Equations
Walt made an extra $9000 last year from a part-time job. He invested part of the money at 9% and the rest at 8%. He made a total of $770 in interest. How much was invested at 8%?
Thank you for taking the time to help me.
Sally
1 solutions

Answer 112076 by Earlsdon(6291) About Me  on 2008-08-19 12:04:11 (Show Source):
You can put this solution on YOUR website!
G'day Sally;
Let x = the amount invested at 8% and the remainder ($9000-x) is invested at 9%
The amount of interest earned on these amounts can be expressed as:
x(0.08) This is amount earned at 8%.
($9000-x)(0.09) This is the amount earned at 9%
The sum (+) of these two amounts is given as $770.00, so you can write the equation to solve for x, the amount invested at 8%
(0.08)x + (0.09)($9000-x) = $770 Simplify and solve for x.
0.08x + $810 - 0.09x = $770 Subtract $810 from both sides.
0.08x-0.09x = -$40 Combine the x's on the left side.
-0.01x = -$40 Finally, divide both sides by -0.01 to get x by itself.
x = $4000
So $4000 was invested at 8% and $9000-$4000 = $5000 was invested at 9%
Let's check the solution:
0.08($4000) + 0.09($5000) = $320 + $450 = $770 The total interest earned.


logarithm/152475: 2ln%28x%5E%281%2F2%29%29-ln%281-x%29=2
1 solutions

Answer 112066 by Earlsdon(6291) About Me  on 2008-08-19 11:23:55 (Show Source):
You can put this solution on YOUR website!
Solve for x:
2%2Aln%28x%5E%281%2F2%29%29-ln%281-x%29+=+2 Apply the power rule to the first term on the left side:a%2Aln%28b%29+=+ln%28b%5Ea%29
ln%28x%29+-+ln%281-x%29+=+2 Now apply the quotient rule to the left side: ln%28a%29-ln%28b%29+=+ln%28a%2Fb%29
ln%28x%2F%281-x%29%29+=+2 Rewrite this in its exponential form: ln%28x%29+=+y---> e%5Ey+=+x
e%5E2+=+x%2F%281-x%29 Multiply both sides by (1-x)
e%5E2%281-x%29+=+x Expand the left side.
e%5E2-e%5E2x+=+x Add e%5E2x to both sides.
e%5E2+=+e%5E2x%2Bx Factor the x on the right side.
e%5E2+=+x%28e%5E2%2B1%29 Divide both sides by %28e%5E2%2B1%29
x+=+e%5E2%2F%28e%5E2%2B1%29 Ths is the exact answer. If you want an approximate answer, then substitute e%5E2+=+7.4 to get:
x+=+7.4%2F8.4
x+=+0.88


Expressions-with-variables/152490: What is the answer to F(x)=x3? I could not find where I could put a small 3 above the x but it means x to the third power.
1 solutions

Answer 112064 by Earlsdon(6291) About Me  on 2008-08-19 10:58:57 (Show Source):
You can put this solution on YOUR website!
What is the answer to: f%28x%29+=+x%5E3?
The answer depends entirely upon the value of x!
Did you forget to include that?


Radicals/152491: This question is from textbook Intermediate Algebra
Can someone help me with this problem. I am stuck on don't know which way to go.
The problem is multiply sqrt of 27b sqrt of 3b^3k and simplify the result.
Thanks for anyone that can help!
1 solutions

Answer 112063 by Earlsdon(6291) About Me  on 2008-08-19 10:56:28 (Show Source):
You can put this solution on YOUR website!
Simplify:
%28sqrt%2827b%29%29%2A%28sqrt%283b%5E3%2Ak%29%29==3b%2A%28sqrt%283b%29%29%2A%28sqrt%283bk%29%29+=+3b%2Asqrt%283b%2A3b%2Ak%29=3b%2Asqrt%283%5E2b%5E2k%29+=+3b%2A3b%2Asqrt%28k%29=9b%5E2sqrt%28k%29


Polynomials-and-rational-expressions/152481: How do you Divide this rational expression: x^2-9/4x+12(Divided by)x-3/6? I dont understannd this at all. Whats the answer?
1 solutions

Answer 112054 by Earlsdon(6291) About Me  on 2008-08-19 09:59:11 (Show Source):
You can put this solution on YOUR website!
Divide:
%28x%5E2-9%29%2F%284x%2B12%29divided by%28x-3%29%2F6Do the first fraction by factoring the numerator and the denominator:
Cancel the indicated factors to leave you with:
%28x-3%29%2F4 Now divide by the second fraction, but remember to change to multiplication and invert the second fraction.
%28cross%28%28x-3%29%29%2F4%29%2A%286%2Fcross%28%28x-3%29%29%29 Cancel the indicated factors to leave you with:
6%2F4 Finally, reduce this fraction to its lowest terms.
3%2F2


logarithm/152408: Hi, my name is Stormy i'm going into 9th grade and I start Wednesday.I have no clue what the logarithm is and i would like too know so that i have a headstart in algebra concept this year. I get all a's and don't want them to drop. This is the first year i did not attend summer school and they learned the logarithm this year. if you could please give me a short explanation of what the logarithm is i would greatly appreciate it.
Thanks again,
Stormy
1 solutions

Answer 112016 by Earlsdon(6291) About Me  on 2008-08-18 20:27:48 (Show Source):
You can put this solution on YOUR website!
You are not alone in being mystified by logarithms!
To understand logarithms, you should be familiar with exponents because they are closely related.
Remember exponents, also called powers?
10%5E2+=+100 Here, the base is 10 and the exponent (power) is 2.
2%5E3+=+8 Here, the base is 2 and the exponent is 3.
So, here's a definition of logarithms:
" The logarithm of a number is the power to which the base of the logarithm must be raised to equal the number"
So a logarithm has a "base".
Commonly, this base is 10, but it can be any number. When the logarithm has a base of 10, it is called a "common logarithm" or "common log" for short.
Let's see how this works:
Let's suppose that we want to find the common log (base 10) of 100.
We would write:
log%28100%29+=+x You could show the base if you wanted to make absolutely sure that your reader undertood which base you were using by:
Log%5B10%5D%28100%29+=+x but, if no base is shown, and the notation is log or Log, then common logarithms are assumed.
What the above equation says is..."x is the power to which the base (10) must be raised to equal 100".
Well, you know that already because 10%5E2+=+100 so x must equal 2, or
Log%5B10%5D+%28100%29+=+2
In fact, you can express the logarithm above in exponential a general form:
b%5Ex+=+100 The base (b) is 10 and x = 2, so...
10%5E2+=+100
In more general terms, let b denote the base, we can write:
Log%5Bb%5D%28x%29+=+y You would read this as: "The log, to the base b, of x = y" and this can be expressed in exponential form as:
b%5Ey+=+x
Let's try a few more numbers, but we will stay with common (base 10) logs for now.
Log%281000%29+=+3 why, because 10%5E3+=+1000
Log%2810%29+=+1 why, because 10%5E1+=+10
Now if you wanted to find the common log of a number that is not a multiple of the base (10), you would then have to resort to a calculator or a table of common logarithms.
For example:
log%283%29+=+0.47712125 approximately. The result is an irrational number (remember those?)
Most scientific or math calculators will have a logarithm key.
This is just an overview but you could log on to any good information site and type in Logarithms and you'd probably get more information on the topic than you could use.


Geometry_Word_Problems/152386: A, B, C, and D are distinct coplanar points, no 3 of which are collinear. If E is a point not in the plane of A, B, C, and D, how many distinct planes are determined by the 5 points?
a. 4
b. 5
c. 6
d. 7
Which answer is correct and why?
1 solutions

Answer 112013 by Earlsdon(6291) About Me  on 2008-08-18 19:27:00 (Show Source):
You can put this solution on YOUR website!
Think about this!
Through any three non-collinear points, there is exactly one plane!
The planes that you identify here must include the point E, so you can list all of the possible combinations of the points, A, B, C, D, with the point E.
E,A,B
E,A,C
E,A,D
E,B,C
E,B,D
E,C,D
So it seems that there are 6 distinct planes determined by the five points if point E is to be included in each one.


Exponents/152377: I am doing exponents in expanded form and have a question:
In the number 1,203,487,386 when I start to expand this to (1 x 10-10)+(2 x 10-9)+ do I include the 0 or leave it out?)
1 solutions

Answer 112011 by Earlsdon(6291) About Me  on 2008-08-18 19:11:28 (Show Source):
You can put this solution on YOUR website!
You should include the zero for completeness, and notice that you start at an exponent of 9:
1,203,487,386 =
1,000,000,000 = 1X10%5E9
200,000,000 = 2X10%5E8
-------------------------
3,000,000 = 3X10%5E6
400,000 = 4X10%5E5
80,000 = 8X10%5E4
7,000 = 7X10%5E3
300 = 3X10%5E2
80 = 8X10%5E1
6 = 6X10%5E0 Recall that 10%5E0+=+1


Angles/152385: This question is from textbook Geometry
I'm not sure how to even begin this problem.
1 solutions

Answer 112010 by Earlsdon(6291) About Me  on 2008-08-18 18:55:06 (Show Source):
You can put this solution on YOUR website!
Unfortunately, I don't have the math book from which your problem is taken.


Exponents-negative-and-fractional/152382: This question is from textbook Algebra structure and method book 1
can you please help me answer: (((10x(2)-30x+20 over x(2)-1
1 solutions

Answer 112009 by Earlsdon(6291) About Me  on 2008-08-18 18:52:40 (Show Source):
You can put this solution on YOUR website!
Presumably you would like to simplify this fraction:
%2810x%5E2-30x%2B20%29%2F%28x%5E2-1%29 Factor the numerator and the denominator.
10%28x%5E2-3x%2B2%29%2F%28x%5E2-1%29
%2810%2Across%28%28x-1%29%29%28x-2%29%29%2F%28%28x%2B1%29cross%28%28x-1%29%29%29 Cancel the indicated factors.
10%28x-2%29%2F%28x%2B1%29


Linear-systems/152381: hello. I am having difficulties with my summer math packet, I am really stuck on the problems that have to do with slope, one of these problems is to determine the slope of the line that passes through (5, 1) and (2, 7) so far, I have determined that it may be 6/-3, I used the y2-y1/x2-x1 formula, but I still sense it may be wrong. . I have even more difficulty when I have to use fractions with it such as (-1/2, -2) and (-3/2, 1), I have completely forgotten everything, and desperatly need help
1 solutions

Answer 112006 by Earlsdon(6291) About Me  on 2008-08-18 18:39:44 (Show Source):
You can put this solution on YOUR website!
You have used the slope formula correctly: m+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 and substiuting the given points, you got:
m+=+%287-1%29%2F%282-5%29
m+=+6%2F%28-3%29 Now you should reduce this fraction to its lowest terms:
m+=+-2
Now let's look at the fractions.
m+=+%281-%28-2%29%29%2F%28%28-3%2F2%29-%28-1%2F2%29%29
m+=+%281%2B2%29%2F%28%28-3%2F2%29%2B%281%2F2%29%29
m+=+3%2F%28-2%2F2%29
m+=+3%2F%28-1%29
m+=+-3


Radicals/152379: This question is from textbook Intermediate Algebra
I am working on this problem and I just need to know if I did it right.
I'm suppose to simplify each expression an if an expression can't be simplified, write "does not simplify.
The problem is 2x^2+2x-12 over x^3+3x^2-4x-12
This is what I did
Factored to 2(x^2+x-6)
Factored to 2(x^2+3x-2x-6)
Factored to 2(x(x+3)-2(x+3))
Factored to 2(x+3)(x-2) also common denominator
2x(x-2)+2*3(x-2)
Simplified to 2x(x-2)+6(x-2)
Factored to 2(x-2)(x+3)
Second part denominator :
Factored to x^2(x+3)-4(x+3)
Factored to (x+3)(x^2-4)
Factored to (x+3)(x+2)(x-2) also common denominator
Expanded x(x+2)(x-2)+3(x+2)(x-2) also simplified
Factored to (x+2)(x-2)(x+3) also simplified
Now the answer I got was 2x(x-2)+6(x-2) over (x-2)(x+3)(x+2). Was this problem done correctly and is it simplified?
Thanks for anyone who can check this.
1 solutions

Answer 112005 by Earlsdon(6291) About Me  on 2008-08-18 18:23:33 (Show Source):
You can put this solution on YOUR website!
To answer your questions...NO! and NO! Let's look at the problem:
Simplify:
%282x%5E2%2B2x-12%29%2F%28x%5E3%2B3x%5E2-4x-12%29
Let's do the numerator first: Factor the trinomial:
2x%5E2%2B2x-12+=+2%28x%5E2%2Bx-6%29 = highlight%282%28x%2B3%29%28x-2%29%29 Your work in this step was ok!
Now the denominator: Factor:
x%5E3%2B3x%5E2-4x-12+=+%28x%5E2-4%29%28x%2B3%29=highlight%28%28x%2B2%29%28x-2%29%28x%2B3%29%29 You correct here as well!
Now we'll put 'em together:
%282%28x%2B3%29%28x-2%29%29%2F%28%28x%2B2%29%28x-2%29%28x%2B3%29%29 At this point, can you see the cancellation possibilities?
= highlight%282%2F%28x%2B2%29%29


Mixture_Word_Problems/152357: Word Problems are so hard for me. I can do them with a calulator, but to write them out in algebriac terms and answering them, I am at a loss.
Here is the word problem:
Samantha needs 20 quarts of 50% antifreeze solution in her radiator. She plans to obtain this by nixing some pure antifreeze with an appropriate amount of 40% antifreeze solution. How many quarts of each should she use?
I was thinking 40x . 50 = 20 or maybe 50x + (40 x 20)
I am so new at math, and it is just confusing me to no end!I don't know how to write it, but normally if it's written out I can answer the problem if it's not too complicated.
I would really appreciate any help on this.
1 solutions

Answer 112000 by Earlsdon(6291) About Me  on 2008-08-18 15:56:13 (Show Source):
You can put this solution on YOUR website!
Some times, with mixture problems such as this one, it might be a little easier if you think in terms of just the antifreeze rather than the mixture.
You are told that Samantha needs 20 quarts of 50% antifreeze. First, change the percentage to its decimal equavalent (50% = 50/100 = 0.5).
Now 50% of 20 quarts of antifreeze mixture is really 0.5 (20) = 10 quarts of pure antifreeze.
The amount of 40% antifreeze mixture to be added is (20-x) quarts, that is this is the amount, added to the x quarts of pure antifreeze to get the 20 quarts.
Now let x = the amount of pure (100% = 1) antifreeze to be added to (20-x) quarts of 40% antifreeze mixture.
The amount of 40% antifreeze mixture is 0.4(20-x) quarts of antifreeze.
Now you can write an equation to solve for x, the number of quarts of pure antifreeze that Samantha needs.
x+%2B+0.4%2820-x%29+=+0.5%2820%29 Perform the indicated multiplication.
x+%2B+8+-+0.4x+=+10 Combine the x's
0.6x+%2B+8+=+10 Subtract 8 from both sides.
0.6x+=+2 Finally, didvide both sides by 0.6 to get x by itself.
x+=+3.33 or x = 3 1/3
So Samantha needs to mix 3 1/3 quarts of pure antifreeze with 20-x = 20-3 1/3 = 16 2/3 quarts of 40% antifreeze mixture to obtain 20 quarts of 50% antifreeze mixture..


Geometry_Word_Problems/152354: Hi,
Can someone please review the following, I did the work I just want to make sure it correct before I submit it.
Thank you for your help.
From the given polynomials, identify the polynomials of degree one.
a. 311y - 5 - 43y Since degree is based on the power of the largest variable (or is degree 0 if everything is constants). You have an expression that contains y to a power of 1. So the degree is 1
b. (11y2)1/2 + 14 ( This is a degree 2)
c. 10 + (19)1/2x (This is not a polynomial)
d. 2 + 15x ( This is a degree 1 polynomial)
e. 52y4 + 7x + 2 ( This is not a polynomial)
f. (68)1y1 (This is a degree 1 polynomial)
g. x3 + 3x – 9 ( This is a degree 3 )
h. (2x)1/2 + 4x – 8 (This is a degree 1)

Solve the following:
1. -2x = 3x + 4
-2x = 3x + 4

5x=4 --------> -5*x/5 = 4/(-5)


= -4
5


2. 3x/4 = 6
3x=6*4 , cross multiply:

3x=24 --------> 3*x= 24*8/3 eliminate 3 and 24
x=8

3. y/6 + 1 = 9
y/6 + 1 = 9

y+6/6=9, cross multiply,

y+6=54
y=54-6
y= 48
6 = -2x/4 , cross multiply,
24= -2x -------> 24 * 12/-2 = -2*x/-2 eliminate like terms 24,-2,-2,-2
x= -12

4. 6 = -2x/4
6 = -2x/4
-2x=6*4
-2x=24
x=24/-2
Answer: x=-12
To proof it I did the following:
6=-2*-12/4
6=24/4
6=6

5. Find f(1) for f(x) = 4x3 - 3x2 - x + 2
The problem gives you a "function of x":
f(x) = 4x3 - 3x2 - x + 2
.
Now, to find f(1), it simply asks you to find the value of f(x) when x=1
.
So I , simply substitute in 1 wherever I see the x and solve:
f(x) = 4x^3 - 3x^2 - x + 2
Substituting I get:
f(1) = 4(1)^3 - 3(1)^2 - 1 + 2
f(1) = 4(1) - 3(1) - 1 + 2
f(1) = 4 - 3 - 1 + 2
f(1) = 6 - 4
f(1) = 2 (so f(1)=2)
Answer: f(1)=2
6. A function gives the value of C as 2 × (22/7) × r. Find C when r = 21 cm and r = 84 cm.
plug in 21 for r:
C = 2 × (22/7) × 21
Answer: C = 132 cm
And plug in 84:
C = 2 × (22/7) × 84
Answer: C = 528 cm

1 solutions

Answer 111998 by Earlsdon(6291) About Me  on 2008-08-18 15:28:32 (Show Source):
You can put this solution on YOUR website!
All of your answers look good except for the first problem, part e.
Given: 52y%5E4%2B7x%2B2 ...You said "This is not a polynomial" Why is it not?
It certainly qualifies as a polynomial (a trinomial in this case) because there are no terms with variables in the denominator and no terms with variables under a radical sign.
This polynomial is of degree 4 because of the 52y%5E4


Linear_Algebra/152346: This question is from textbook
How do you find the slope with only one point to work with? The first point is (3,4). The problem I am trying to solve is: Consider the semicircle of radius 5 centered at (0,0) as shown in the figure. Find an equation of the line tangent to the semicircle at the point (3,4). (hint: A line tangent to a circle is perpendicular to the radius at the point of tangency.)
1 solutions

Answer 111994 by Earlsdon(6291) About Me  on 2008-08-18 15:08:37 (Show Source):
You can put this solution on YOUR website!
I don't see the figure you allude to but it's easy enough imagine what it looks like.
In your semicircle, consider the radius from the center to the point of tangency (3, 4). This radius has a slope of m+=+4%2F3 (rise = 4 over run = 3). Now any line that is perpendicular to this radius. eg, the tangent line at (3, 4), will have a slope that is the negative reciprocal of the slope of this radius. So the slope of the tangent line will be m+=+-3%2F4
So now you can write:
y+=+%28-3%2F4%29x%2Bb But of course, you still need to find the value of b, the y-intercept, so substitute the x- and y-coordinate values of the point of tangency (3, 4) into this equation and solve for b.
y+=+%28-3%2F4%29x%2Bb Substitute x = 3 and y = 4
4+=+%28-3%2F4%29%283%29%2Bb Solve for b.
4+=+-9%2F4+%2B+b
b+=+25%2F4
So your final equation would be:
y+=+%28-3%2F4%29x%2B25%2F4 or, if you multiply through by 4 to clear the fractions, it becomes:
4y+=+-3x%2B25


Miscellaneous_Word_Problems/152337: write 1024 in exponentail notation
1 solutions

Answer 111982 by Earlsdon(6291) About Me  on 2008-08-18 11:51:55 (Show Source):
You can put this solution on YOUR website!
1024+=+1024%5E1
1024+=+32%5E2
1024+=+4%5E5
1024+=+2%5E10
Or did you mean "Scientific notation"?
1024+=+1.024%2A10%5E3


Graphs/152335: Hey, I really need some help on this problem.. I just can't understand it. If you could help me I would really appricate it. Thanks in advance.

Write an equation for the line that is parallel in the given line and that passes through the given point.

#58) y = -3x ; (3,0)
1 solutions

Answer 111981 by Earlsdon(6291) About Me  on 2008-08-18 11:42:28 (Show Source):
You can put this solution on YOUR website!
An equation for the line that is parallel to the line: y = -3x and which passes through the point (3, 0).
First, you should recall that parallel lines have the same slope.
The given line has a slope: m = -3, so the new line will have a slope of: m = -3.
So you can start by writing:
y = -3x+b Now you need to find the value of b, the y-intercept. This can be done by substituting the x- and y-coordinate values of the given point (3, 0) into the equation y = -3x+b and solving for b.
0 = -3(3) + b
0 = -9 + b
b = 9
Now you can write the final equation of the line that is parallel to the line whose equation is y = -3x and which passes through the point (3, 0)
highlight%28y+=+-3x%2B9%29


Exponential-and-logarithmic-functions/152229: how do i solve this
e^x + e^x+1 =250
1 solutions

Answer 111906 by Earlsdon(6291) About Me  on 2008-08-17 12:52:01 (Show Source):
You can put this solution on YOUR website!
It's not clear how this problem is to be read!
1) e%5Ex%2Be%5Ex+%2B+1+=+250 or
2) e%5Ex%2Be%28x%2B1%29+=+250 I suspect that this is what you wanted, so let's go with it.
e%5Ex%2Be%5E%28x%2B1%29+=+250 Substitute e%5E%28x%2B1%29+=+e%5Ex+%2A+e%5E1
e%5Ex%2Be%5Ex%2Ae+=+250 Factor out e%5Ex.
e%5E%28x%29%281%2Be%29+=+250 Divide both sides by %281%2Be%29
e%5Ex+=+250%2F%281%2Be%29 Take the natural log of both sides.
ln%28e%5Ex%29+=+ln%28250%2F%281%2Be%29%29 Substitute: ln%28e%5Ex%29+=+x
x+=+ln%28250%2F%281%2Be%29%29
x+=+ln%28250%2F3.72%29
x+=+ln%2867.235355%29
x+=+4.21 Approximately.


Polynomials-and-rational-expressions/152236: Could someone please show me how to solve this equation.
Multiply
%28x%5E8%2Bx%5E7%29%2A%28x%5E8%2Bx%5E7-x%5E6%29
1 solutions

Answer 111905 by Earlsdon(6291) About Me  on 2008-08-17 12:28:13 (Show Source):
You can put this solution on YOUR website!
Let's use a modified FOIL (First-Outer-Inner-Last) method to multiply"
Now simplify this - remembering that when you multiply factors with the same base (x in this case) you will add the exponents of the factors.
Now combine like-terms.
x%5E16%2B2x%5E15-x%5E13 ...and this could be simplified to:
x%5E13%28x%5E3%2B2x%5E2-1%29


Average/152106: This question is from textbook
I'm not sure if this is where I need to ask for help with this problem but I would really be thankful for anyone's assistance.
A book is opened. The product of the two facing page numbers is 9506. What are the numbers of the pages? Explain.
I set it up like this:
9506/2 = 4753 since on page is even and the other odd numbered I then continued 4753-1 = 4752. The pages are numbered 4752 and 4753 but this equals 9505 so it is incorrect.
What do you think? Thanks
1 solutions

Answer 111809 by Earlsdon(6291) About Me  on 2008-08-15 21:17:48 (Show Source):
You can put this solution on YOUR website!
You could try this:
Let x = the left page number and x+1 = the next consecutive page number.
You can write:
%28x%29%28x%2B1%29+=+9506 The product (this is a result of multiplying) of the consecutive page numbers is 9506
x%5E2%2Bx+=+9506 Subtract 9506 from both sides.
x%5E2%2Bx-9506+=+0
The roots are:
x = 97
x = -98
So from this, the page numbers are 97 and 98
The problem I have with this answer is that in most books, their left page numbers are even numbers, not odd numbers.


Rectangles/152104: This question is from textbook
Okay here is a tough one, for me anyway. I would appreciate some help with this problem:
You have a sheet of 8.5 x 11 inch paper. You need to measure exactly six inches. You don't have a ruler or other measuring device. Can you measure exactly six inches using the sheet of paper? Explain.
Thanks to any and all who help.
1 solutions

Answer 111806 by Earlsdon(6291) About Me  on 2008-08-15 20:33:47 (Show Source):
You can put this solution on YOUR website!
You start by carefully folding down one corner of the 8.5 by 11 sheet of paper so that the top of the sheet is accurately alligned with the side of the sheet.
Crease the paper at the fold so that it maintains its shape (a triangle).
Now you fold up the bottom of the sheet (this has the shape of a rectangle with dimensions 8.5 by 2.5. The 2.5 comes from the 11.5-inch side minus the 8-inch side that was folded down in the first step.
Now you have a side of the twice-folded sheet that measures 6 inches, if you have folded very carefully and if your sheet was really 8.5 by 11 inches.


expressions/152073: -20-3x+3x^2=0
I can't seem to find the right way to factor it!
1 solutions

Answer 111789 by Earlsdon(6291) About Me  on 2008-08-15 15:03:18 (Show Source):
You can put this solution on YOUR website!
Perhaps that is because the trinomial -20-3x%2B3x%5E2=0 is not factorable...in other words, it's prime.
Let's rearrange the trinomial so that it's in standard form:
3x%5E2-3x-20+=+0
The factors, if there were any, would take the form:
%283x%2Bm%29%28x%2Bn%29+=+0 and you need to have m*n = -20 and 3n+m = -3
The factors of -20 are:
-20 = -1*20 or 1*(-20) and 3(-1)+20 = 17, 3(1)+(-20) = -17
-20 = -2*10 or 2*(-10) and 3(-2)+10 = 4, 3(2)+(-10) = -4
-20 = -4*5 or 4*(-5) and 3(-4)+5 = -7, 3(4)+(-5) = 7
So, as you can see, there is no way to get a -3 from combining the factors of -20.
The trinomial is prime!


Linear-systems/152079: I need help with this one question i have been stuck on for a few days now here it is.
A process of elimination.
6x+2/3y= 9
2x+2/3y= 7
i dont have a text book number because it is in a module book
1 solutions

Answer 111786 by Earlsdon(6291) About Me  on 2008-08-15 14:36:37 (Show Source):
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Solve:
6x%2B%282%2F3%29y+=+9
2x%2B%282%2F3%29y+=+7 Subtract the second equation from the first equation to eliminate the y.
4x+=+2 Divide both sides by 4.
x+=+1%2F2 Now substitute this value of x into either of the two given equations to solve for y. The second equation will work nicely.
2%281%2F2%29%2B%282%2F3%29y+=+7 Simplify.
1%2B%282%2F3%29y+=+7 Subtract 1 from both sides.
%282%2F3%29y+=+6 Multiply both sides by the multiplicative inverse of 2%2F3, that's 3%2F2
%283%2F2%29%282%2F3%29y+=+6%283%2F2%29
y+=+9
The solution is: (1/2, 9)


Finance/152077: 132.48/x=147.12
Can you give me step by step to solve this, i did it with a calculator and got the answer, just forgot how to actually solve.
1 solutions

Answer 111785 by Earlsdon(6291) About Me  on 2008-08-15 14:17:45 (Show Source):
You can put this solution on YOUR website!
Solve for x:
132.48%2Fx+=+147.12 Multiply both sides by x
132.48+=+147.12%28x%29 Now divide both sides by 147.12
x+=+132.48%2F147.12 Perform the indicated division on the right side.
x+=+0.9 Approximately.


Radicals/151986: How would I solve
(z+2)^-(2/3) = 3
i dont know if this is easy to understand but the first equation is to the negative two thirds power.
1 solutions

Answer 111728 by Earlsdon(6291) About Me  on 2008-08-14 22:39:55 (Show Source):
You can put this solution on YOUR website!
Solve for x:
%28z%2B2%29%5E%28-2%2F3%29+=+3 Raise both sides to the power of %28-3%2F2%29
%28%28z%2B2%29%5E%28-2%2F3%29%29%5E%28-3%2F2%29+=+3%5E%28-3%2F2%29 To the left side, apply the "product rule for exponents" %28M%5Ea%29%5Eb+=+M%5E%28ab%29
%28z%2B2%29+=+3%5E%28-3%2F2%29
z%2B2+=+%281%29%2F%283%5E%283%2F2%29%29 This is supposed to be: 1over3%5E%283%2F2%29 and 3%5E%283%2F2%29+=+sqrt%2827%29
z%2B2+=+1%2Fsqrt%2827%29 Multiply top and bottom bysqrt%2827%29
z%2B2+=+sqrt%2827%29%2F27 Now subtract 2 from both sides.
z+=+sqrt%2827%29%2F27+-+2
z+=+%28sqrt%2827%29-54%29%2F27


Miscellaneous_Word_Problems/151991: I don't even know where to begin on this question. Can you help me please? Thanks!
Find P(-1/2) if
P(x) = 2x4 + x3 + 12

1 solutions

Answer 111727 by Earlsdon(6291) About Me  on 2008-08-14 22:20:20 (Show Source):
You can put this solution on YOUR website!
Find: P%28-1%2F2%29 if:
P%28x%29+=+2x%5E4%2Bx%5E3%2B12 Simply replace the x's with -1%2F2 and evaluate.
P%28-1%2F2%29+=+2%28-1%2F2%29%5E4%2B%28-1%2F2%29%5E3%2B12
P%28-1%2F2%29+=+2%281%2F16%29%2B%28-1%2F8%29%2B12
P%28-1%2F2%29+=+2%2F16-1%2F8+%2B+12 Reduce 2%2F16+=+1%2F8
P%28-1%2F2%29+=+1%2F8-1%2F8%2B12 Simplify.
P%28-1%2F2%29+=+12