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rapaljer answered: 4664 problems
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Numeric_Fractions/13301: Could u help me on finding the missing factors please
1 solutions

Answer 6647 by rapaljer(4667) About Me  on 2005-09-29 22:31:26 (Show Source):
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I don't see ANY factors in this problem!!! It looks to me like ALL the factors are missing!!

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Quadratic_Equations/13295: Simplifify
6x^2y^2 + 11xy + 4 all divided by
9x^2y^2 + 9xy - 4
I've tried and i cant get it to simplify, does it even simplify
1 solutions

Answer 6645 by rapaljer(4667) About Me  on 2005-09-29 22:29:36 (Show Source):
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You'll have to factor the numerator and denominator in order to reduce the fraction. It just so happens (by chance???) that they both factor as trinomials. It may be some tough factoring, but they do factor.

+%286x%5E2y%5E2%2B11xy%2B4%29%2F%289x%5E2y%5E2%2B9xy-4%29+

%28%282xy+%2B4%29%2A%282xy%2B1%29+%29%2F%28%283xy%2B4%29%2A%283xy-1%29%29+

You can divide out the factor of (3xy+4).

Final answer: +%282xy%2B1%29%2F%283xy-1%29+

R^2 at SCC


Numeric_Fractions/12283: (2x+3)/x + 4/(x-1) =0
Solve for x.
I don't know if I'm on right track with this.
I ended up with a quadratic and using formula got x=-2+or-sqrt7.
Grateful for any advice
1 solutions

Answer 6631 by rapaljer(4667) About Me  on 2005-09-29 20:10:24 (Show Source):
You can put this solution on YOUR website!
I don't know what you did to get your answer, but I didn't get that.

First, this is an equation, and there are several ways to solve it. I think the easiest way to solve it, since it is equal to zero, add the second fraction 4%2F%28x-1%29+ to both sides and write this as a fraction equal to the negative of a fraction. As I said, this is NOT the only way, but I think it will be the easiest to explain and easiest to understand:
%282x%2B3%29%2Fx+%2B+4%2F%28x-1%29+-+4%2F%28x-1%29+=0-+4%2F%28x-1%29+
+%282x%2B3%29%2Fx+=+-4%2F%28x-1%29+

Remember a%2Fb=+c%2Fd means that a%2Ad+=+b%2Ac

So,
+%282x%2B3%29%2Fx+=+-4%2F%28x-1%29+ means that %282x%2B3%29%2A%28x-1%29=+-4%2Ax+

Multiplying it out:
2x%5E2%2Bx-3+=+-4x

Set equal to zero by adding +4x to each side:
2x%5E2+%2Bx+-+3+%2B+4x+=+-4x+%2B+4x
2x%5E2+%2B+5x+-+3+=+0

As CHANCE would have it (yeah, right!) THE TRINOMIAL FACTORS!!
+%282x+%2B+1%29%2A%28x-3%29+=+0

First solution:
2x%2B1+=0
2x+=+-1+
x=+1%2F2

Second solution:
x-+3=+0
x=+3

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Expressions-with-variables/13221: A STUDENT WAS REASERCHING ALASKAN GLACIERS. HE USED DIFFERENT SOURCES TO FIND THE SPEED AT WHICH 3 GLACIERS ARE MOVING
Glacier Speed
Sliding 4per day
Hanging 3 inches per hour
Drifting 6*10 negative 5 miles per hour
and i have to convert them to all the same
to see which uis moving at the greatest speed? Please help im really stuck on how to do the equation parts to convert them all to the same #'s like feet per day i thought it would be best if gone into 4 fette per day but i got the wrong answer
Please Help Thanks

1 solutions

Answer 6623 by rapaljer(4667) About Me  on 2005-09-29 18:58:39 (Show Source):
You can put this solution on YOUR website!
SPEAKING OF ALASKA, BE SURE TO SEE my website and check out OUR PICTURES FROM ALASKA!! There are PICTURES OF REAL GLACIERS (the pictures look TOO GOOD to be real, but believe me, we were there!! They ARE REAL!!) Click on my tutor name here at algebra.com, and look for "Pictures from Alaska". Isn't it GREAT to see MATH all around us in life, EVEN IN GLACIERS!!!

I'm not sure about your first glacier, since you said it is sliding at 4 per day. I don't know 4 what per day? Is that supposed to be 4 feet per day?

The second glacier is moving at 3 inches per hour, which is 3*24 = 72 inches per day, then divide by 12 to convert it to 6 feet per day.

The third one is 6%2A10%5E-5+miles per hour. Multiply this times 5280 to change it to feet per hour and then multiply by 24 hours to see how far it moves in a day. This turns out to be (with a calculator!!) 6%2A10%5E-5%2A5280=+.3168 feet per hour , then times 24 to change it to 7.6032 feet per day.

The greatest speed looks like the last one which is about 7.6 feet per day.

R^2 at SCC


Equations/13223: If Loius's savings were increased by 4 times his savings, the result would be $25,000. how much has he saved?
1 solutions

Answer 6619 by rapaljer(4667) About Me  on 2005-09-29 18:39:45 (Show Source):
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Let x= amount of his savings

There may be two ways to interpret this: Were his saving increased BY 4 times his savings? I think that must mean that he ADDS 4x to his present savings of x.

The equation is
x + 4x = 25000
5x = 25000
x= $5000

Check: If his savings of $5000 are INCREASED BY 4 times this amount (which by the way is $20,000), then the result is $25,000. I'm almost sure this is the way the problem is intended to be interpreted.

R^2 at SCC


Linear-equations/13214: How would you solve y=-1/3+23/3 then graph it?

1 solutions

Answer 6617 by rapaljer(4667) About Me  on 2005-09-29 18:22:38 (Show Source):
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Do you mean y= -1/3 x + 23/3??? If so, then you need to start with the y-intercept at the point 23/3, which is almost up to 8 units.

From this point measure off a slope of -1/3. This is to say, it is a RISE of -1 and a run of 3. So from the point that you just graphed on the y axis, and measure DOWN 1 unit, then move 3 unit to the right, and put a point. Connect the two points and it should look like this:
+graph+%28+300%2C300%2C+-10%2C+10%2C+-10%2C+10%2C+%28-1%2F3%29%28x%29+%2B+23%2F3%29+

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Percentage-and-ratio-word-problems/13219: Mr. Garza's annual income has gone from $32,000 to $48,000 in 6 years. By what percent has his annual income increased?
1 solutions

Answer 6616 by rapaljer(4667) About Me  on 2005-09-29 18:08:17 (Show Source):
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First find the amount of increase. Since the income went from $32000 to 48000, this means that the amount of increase is $16000. Percent of increase is always a comparison of the amount of increase to the ORIGINAL amount, which is $32000.

Percent of increase = +%28Amount+Increase%29%2F+Original+Amount%29+
= +16000%2F32000 = 1%2F2 = 50%

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Reduction-of-unit-multipliers/13213: Shandra combined the following juices to make fruit punch: 800ml applt juice, 500ml pineapple juice, 1,000ml of orange juice and 200ml of grape juice. What was the total amount of fruit punch made in liters?
1 solutions

Answer 6615 by rapaljer(4667) About Me  on 2005-09-29 18:03:52 (Show Source):
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First add up ALL the juice in ml. That would be 2500 ml. Then convert to liters.

I use what I call the "Metric Line", starting from left to right with
kilo, hecto, deca, basic unit (in this case liters), deci, centi, milli. When converting from one unit to another, you must move the decimal to the left or right, depending upon what you are converting to what. Count the number of units that you move from left to right or right to left, and move the decimal that many places to the left or right.

In this case you are converting from milli to the basic unit (liters), which is moving 3 places to the left. You must therefore move the decimal three places to the left, so 2500 ml = 2.5 liters.

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Inequalities/12909: WHAT IS THE SOLUTION OF THE INEQUALITY 8-3x<-3(1+x)+1
a.all real numbers b.no real numbers c.x>2/3 d.x<-11/6
1 solutions

Answer 6614 by rapaljer(4667) About Me  on 2005-09-29 17:51:52 (Show Source):
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8-3x<-3(1+x)+1

Use distributive property to remove the parentheses:
8-3x < -3- 3x + 1

Combine like terms on each side:
8-3x < -2 - 3x

Add +3x to each side in an attempt to get all variable terms on the left side:
8-3x+3x < -1 - 3x + 3x
8 < -1

Since there are NO VARIABLES left in the equation, you can't solve for x as you do in most equations. In this case, all you have left is 8<-1, which is NOT TRUE. In fact, it is NEVER true. This means that no matter what x is, 8 will NEVER be less than -1. This means that there IS NO SOLUTION!

The final answer is b. No Real Numbers.

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Circles/12974:
Find the domain of

y = √x –2







1 solutions

Answer 6537 by rapaljer(4667) About Me  on 2005-09-28 15:12:56 (Show Source):
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I'm not sure exactly what you mean by this. If you mean y=sqrt%28x%29-+2 which is technically what you have given, it means that x must be greater than or equal to zero. Domain is in interval notation: [0, infinity)

If you meant y=sqrt%28x-2%29, this means that x-2 must be greater than or equal to zero. If you add 2 to each side of the inequality, you get x must be greater than or equal to 2. Domain for this, in interval notation, would be [2, infinity).

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Circles/12975:
Find the domain of

y = 7x2 – 14/12x2 + 20











1 solutions

Answer 6534 by rapaljer(4667) About Me  on 2005-09-28 14:52:07 (Show Source):
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Are you saying:
y = %287x%5E2-14%29%2F%2812x%5E2%2B20%29+
If so, the domain consists of all values of x except that the denominator must NEVER be zero. The denominator consists of taking a value of x, squaring it, multiplying that result by 12 and then adding 20. By looking at this you can see that squaring a number will never be negative. Multiplying by 12 and then adding 20 will certainly always give you a positive, never a ZERO, result.

Therefore the answer for domain is all real values, since the denominator can never be zero.

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Age_Word_Problems/12980: Kenneth's age is 5 yrs older than Alvin. Find there present ages if the product of Kenneth's age 4 yrs. from now and Alvin's age 5 yrs. ago is 51.
1 solutions

Answer 6532 by rapaljer(4667) About Me  on 2005-09-28 14:24:46 (Show Source):
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Let x = Alvin's age
x+5 = Kenneth's age
x+5 + 4 = x+9 = Kenneth's age 4 yrs from now
x-5 = Alvin's age 5 years ago.

Equation:
Product of (Kenneth 4 years from now)x (Alvin 5 years ago) = 51
(x+9)(x-5) = 51
x%5E2%2B4x+-+45+=+51
x%5E2+%2B+4x+-+96+=+0

Guess what! It factors!!
+%28x%2B12%29%28x-8%29+=+0
x= -12, x= 8

An age cannot be negative, so
x= 8 Alvin's age
x+5 = 13 Kenneth's age

Check: In 4 years Kenneth will be 17, and 5 years ago, Alvin was 3. The product of 17*3 is 51.
It checks.

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Expressions-with-variables/12987: i really need ur help solving this equation: 21x+3=121
1 solutions

Answer 6529 by rapaljer(4667) About Me  on 2005-09-28 14:08:27 (Show Source):
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21x+3=121

Add -3 to each side:
21x+3-3=121-3
21x = 118

Divide both sides by 21:
%2821x%29%2F21=118%2F21
x=+118%2F21

What an UGLY answer! Life doesn't always come out even, does it? In this case, the fraction doesn't even reduce!! How sad!!

R^2 at SCC


Linear-systems/12985: Hello:
I really need your help. I have tried all possible ways to solve this equation but I am confused on how to start to solve it. Here is the question:
Find the point of intersection of the given straight lines.
x - 4y = -2
x + 2y = 4
Please help me with this problem. Thank you.
1 solutions

Answer 6527 by rapaljer(4667) About Me  on 2005-09-28 14:04:14 (Show Source):
You can put this solution on YOUR website!
There are several ways to do this. The elimination method usually works well when the equations are both in standard form, as in this case.
x - 4y = -2
x + 2y = 4

In order to eliminate the x variable, multiply the first equation by -1, and rewrite the second equation as it is:
-x + 4y = 2
x + 2y = 4

Now add these two equations together giving you
6y = 6
y=1

Substitute the y = 1 back into either equation, say the first one:
x - 4y = -2
x - 4(1) = -2
x-4 = -2

Add 4 to each side:
x-4+4 = -2 + 4
x=2

Check in the second equation, by letting x= 2 and y = 1:
x + 2y = 4
2 + 2(1) = 4
It checks!

R^2 at SCC



Linear-systems/12580: I don't get qestion number 19 page 134 of algebra 1
1 solutions

Answer 6398 by rapaljer(4667) About Me  on 2005-09-26 02:01:12 (Show Source):
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And YOU think the tutors at algebra.com are SO GOOD we can solve a problem just from the page number and the problem number? Maybe if you gave us the answer, we could tell you what the problem was???

Forgive my cynicism. It's late! Or is that EARLY??

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Functions/12592: hi can you help me with this -6/5<-4x
1 solutions

Answer 6397 by rapaljer(4667) About Me  on 2005-09-26 01:58:04 (Show Source):
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I personally think you are better off getting the variables to the LEFT side when solving inequalities, so add 4x to each side and add 6/5 to each side.

4x < 6/5

The divide both sides by 4, or what might work better in this case is to multiply both sides by 1/4:

%281%2F4%29%2A+%284x%29+%3C+%281%2F4%29%2A+%286%2F5%29
x+%3C+6%2F20
x%3C+3%2F10

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Geometry_Word_Problems/12577: The measures of two complementary angles are 12q-9 and 8q+14. Find the measures of the angles.
1 solutions

Answer 6396 by rapaljer(4667) About Me  on 2005-09-26 01:42:45 (Show Source):
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12q-9 + 8q+14 = 90
20q + 5 = 90
20q= 85
q = 85/20 = 4.25

The angles are 12q-9= 12(4.25) - 9 = 51-9= 42 degrees
8q + 14 = 8(4.25) + 14 = 34 + 14 = 48 degrees

Check by adding 42 + 48 = 90 degrees.

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Expressions-with-variables/12584: I don't get how you do fractions like A/2+5=10 I get all confussed what do I do?
1 solutions

Answer 6395 by rapaljer(4667) About Me  on 2005-09-26 01:37:39 (Show Source):
You can put this solution on YOUR website!
If you really don't like fractions, then multiply both sides by the denominator which is 2, and get rid of it:

A%2F2+%2B+5+=+10

2%2A%28A%2F2%29+%2B+2%2A5+=+2%2A10

The 2 divides out in the first term, leaving:
A+%2B+10+=+20

Now just subtract 10 from each side:
A%2B10-10+=+20-10
A=+10

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Mixture_Word_Problems/12601: How many gallons of pure antifreeze must be added to 20 gallons of 25% antifreeze to get a mixture that is 40% antifreeze
1 solutions

Answer 6394 by rapaljer(4667) About Me  on 2005-09-26 01:16:36 (Show Source):
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Let x = amt of pure antifreeze to be added
You are adding this to 20 gallons of 25% and you will end up a total mixture of x+ 20 at 40%.

The equation is
.25(20) + x = .40(x+20)
5 + 1.00x = .40x + 8
1.00x - .40x = 8 - 5
.60x = 3

x+=+3%2F.6+=+30%2F6+=+5+gallons

Does it check?? (It is VERY late in Florida, here! I don't guarantee my work or my spelling at this hour!!}}}

R^2 at SCC


Quadratic_Equations/12588: I'm supposed to find a family of quadratic equations passing through the points (1,0) and (-1,-2), using the general form y=Ax^2+Bx+C. So far, here's what I got:
1) Plugged in both points to the general form, giving me 2 distinct equations:
0=A+B+C
0=A-B+C+2
2) Made them equal to each other, giving me B=1
3) Subbed B=1 into either equation to get A=-C-1 and C=-A-1
Now this is the point where I get stuck, since if I use both B=1 and A=-C-1 to get the final two variables, I end up with nothing. Please help, and thanks so much!
-Bing
1 solutions

Answer 6393 by rapaljer(4667) About Me  on 2005-09-26 00:54:36 (Show Source):
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You are correct. Remember that you are trying to find a family of parabolas, which means that there are perhaps an infinite number of such parabolas. This is what happens when you have three unknowns and only two conditions (i.e., equations) to satisfy.

Both equations come down to A + C = -1. So, let B=1, and solve for either C or A in terms of the other. Say, C= -A -1.

The equation is the family of parabolas:
y=+Ax%5E2+%2B+Bx+%2B+C

y+=+Ax%5E2+%2B+x+-A+-1, where A represents any non-zero number. Of course, if A = 0, then it is NOT a parabola.

Any other value of A should give you points that include (1,0) and (-1,-2).

For examples, let A = 1: y+=+x%5E2+%2B+x+-2 Do both points satisfy this? If x =1, then y= 0, and if x=-1, then y =-2.

Let A = 2: (((y = 2x^2 +x -3}}}

Let A = -1: y+=+-x%5E2+%2B+x+

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Inequalities/12596: please help me solve this inequality: (x+2)(x-1)(x-3)<= 0
1 solutions

Answer 6392 by rapaljer(4667) About Me  on 2005-09-26 00:34:06 (Show Source):
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I've seen that you have been trying for a long time to get an answer to this one. I'm not sure the best way to explain it to you, since the graphing calculator is the BEST way to do it. Not knowing your background, I'll try a general explanation of sorts.

First solve the equation to find out where (x+2)(x-1)(x-3) = 0. This happens at three points on a numberline, at x= -2, x= 1, and at x=3. Now, the question is actually where will the product of these numbers be LESS THAN or EQUAL to ZERO. So you know THREE solutions right off the bat.

Now, you must realize that, since this is an INEQUALITY, it could be any of the intervals that are created by these three endpoints. If you graph the three points on a numberline, you will notice that these THREE numbers divide the numberline into FOUR intervals (always one more interval than endpoints!). What you need to do is to TEST out ONE POINT in each of the intervals.

Start with the values on the numberline to the RIGHT of x=3. For example, if you took 4 or any other number larger than x=3, and subsitute into the inequality: (x+2)(x-1)(x-3) <=0, it will be positive number times positive times a positive number, which is NOT less than zero.

Next, test a point that is between 1 and 3, like for example 2. If you subsitute x= 2, it comes out to be a product that IS less than zero.

Next, test a point that is between -2 and 1. That will be a positive, so it is NOT less than zero.

Finally, test a point that is less than -2, and the result will be a product that is NEGATIVE, so this interval works.

Therefore the answer is all values from negative infinity to -2 including the -2, and also from 1 to 3 including those endpoints.

It has occurred to me that what I just wrote is probably not a very clear explanation. Let's try the graphing method. You must graph y=(x+2)(x-1)(x-3), and find all values of x for which points on the graph are ON or BELOW the X-axis.
graph%28300%2C300%2C+-5%2C5%2C-10%2C10%2C+%28x%2B2%29%28x-1%29%28x-3%29+%29+

From this graph you can see that the graph is BELOW the x-axis from negative infinity to -2, and again from 1 to 3. Of course include the endpoints, but don't EVER include infinity.

R^2 at SCC

P.S. Do you see why no one wanted to answer this question???


Polynomials-and-rational-expressions/12598: please help me solve these following questions:
simplify the following radicals. :
squar foot of 50=?
squar foot of 325=?
squar foot of 96=?
squar foot of 256=?
1 solutions

Answer 6391 by rapaljer(4667) About Me  on 2005-09-26 00:14:11 (Show Source):
You can put this solution on YOUR website!
What do you mean "squar foot"??? Do you mean square root??

To find a square root, you need to know the perfect squares, and find the largest perfect square that will divide evenly into the given number. The following ar examples of this concept. For additional explanation see my Lesson Plans in algebra.com on Square Roots, or see my website under Basic Algebra, Samples of Basic Algebra One Step at a Time, and Chapter 5.

sqrt%2850%29+=+sqrt%2825%29%2Asqrt%282%29=+5%2A+sqrt%282%29

sqrt%28325%29+=+sqrt%2825%29%2Asqrt%2813%29=+5%2A+sqrt%2813%29

sqrt%2896%29+=+sqrt%2816%29%2Asqrt%286%29=+4%2A+sqrt%286%29

sqrt%28256%29+=+16 because that one comes out even: 16%5E2=+256.

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Travel_Word_Problems/12597: A starts running at Speed 5 km/h at 8 am. after 30 minutes B starts running from the same point in the same direction at Speed 6 km/h. At what time, B will catch A.
Sir I solved it like this. Pl. correct me where I was wrong. The answer is 11 am (3 hrs).
Speed of A= 5 KM/h
Distance travelled in 30 minutes= 2.5 kms.
Relatve speed of B w.r.t. A = (6-5)= 1 km/h.
Distance of 1 Km is covered in 1 hr by B.
therefore gap of 2.5 kms will be covered by B in 1 * 2.5= 150 minutes (2 hrs 30 minutes) whereas the answer is 3 hrs. Pl. correct me.


1 solutions

Answer 6389 by rapaljer(4667) About Me  on 2005-09-26 00:06:36 (Show Source):
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You are absolutely CORRECT!! You said that B will catch A in 2 hours 30 minutes, which IS at 11:00 a.m!! You must have forgotten that B started a half hour later than A, which would be starting at 8:30 a.m. for B. Three hours is the time for A to be caught! Two and a half hours is the time for B to do the catching!! BOTH happen at the same time--11:00 a.m.!!

R^2 at SCC


Numbers_Word_Problems/12585: A store keeper goes to the bank to get $10 worth of change. He requests twicew as many quarters as half dollars, twice as many dimes as qurters, 3 times as many nickles as dimes, and no pennies or dollars. How many of each coin did the storekeeper get?
1 solutions

Answer 6386 by rapaljer(4667) About Me  on 2005-09-25 23:55:39 (Show Source):
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Let x = number of half dollars
2x = number of quarters
2(2x) = 4x = number of dimes
3(4x) = 12x = number of nickels

Total value, multiply number of coins times the value of each coin in cents, and the total value of the coins is $10 or 1000 cents. (Doesn't it make "cents" to do it this way??)

50(x) + 25(2x) + 10(4x) + 5(12x) = 1000
50x + 50x + 40x + 60x = 1000
200x = 1000
x= 5 Half dollars
2x = 10 Quarters
4x = 20 Dimes
12x = 60 Nickels

Check: Does it add up to $10.00??? You tell me!!

R^2 at SCC


logarithm/12591: Please help with this problem: 3 log 3 x=5 (the second "3" is under the word "log"). I can't seem to follow the pattern on my textbook. I would love to see the steps to working out this problem. thanks!
1 solutions

Answer 6385 by rapaljer(4667) About Me  on 2005-09-25 23:28:04 (Show Source):
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3+%2Alog%283%2Cx%29+=+5+

There are probably several ways to go about this. I'd say to divide both sides by 3, and get
log%283%2Cx%29+=+5%2F3

Next use the basic definition of logarithms to convert to exponential form. Remember the definition says +log%28b%2Cx%29+=+y means b%5Ey+=+x?

In the same way, log%283%2Cx%29+=+5%2F3 means that 3%5E%285%2F3%29+=+x

What you are trying to find is x, and that's it!! x = 3%5E%285%2F3%29+.

Is that enough, or you could probably rewrite this as 3%2A+%283%5E%282%2F3%29+%29+ which means 3%2A+%28+root%283%2C9%29+%29, but that's getting carried away if you ask me. Easier to calculate it and say approximately 6.24.

R^2 at SCC


Quadratic_Equations/12429: Question:
x²+y²=13
2x+y=1
I then tried to solve by substitution:
y=1-2x
x²+(1-2x)²=13
I then got a bit muddled up and wasn't sure how to expand (1-2x)²
But the answer i got would not factorise into two brackets so i decided to use the quadratic formula:
-b+/- sqrt ......
but this did not get the correct answer of:
x=-1.2, y=3.4
x=2, y=-3
Please help me because i don't have a clue what to do next!
1 solutions

Answer 6327 by rapaljer(4667) About Me  on 2005-09-24 09:32:32 (Show Source):
You can put this solution on YOUR website!
What you did so far, looks right so far. Let's expand the square of the binomial:

y=1-2x
x²+(1-2x)²=13
x%5E2+%2B+1+-+4x+%2B+4x%5E2+=+13
5x%5E2+-+4x+-+12=+0
By quadratic formula
x+=+%284+%2B-+sqrt%2816-4%2A5%2A%28-12%29%29%29%2F%282%2A5%29
x+=+%284+%2B-+sqrt%2816%2B240%29%29%2F10
x+=+%284+%2B-+sqrt%28256%29%29%2F10

This is the square root of a perfect square, which means that the original equation DOES factor, and the quadratic formula was not necessary in this case. However, you are almost there now, so might as well finish it.
x=+%284+%2B-+16%29%2F10

x=+%284%2B16%29%2F10+=+20%2F10+=+2
x=+%284-16%29%2F10+=+%28-12%29%2F10+=+%28-6%29%2F5

Then solve for y using y = 1-2x
If x= 2, y = 1-2*2= -3

If x+=+-6%2F5, then y+=+1+-+2%2A%28%28-6%29%2F5%29= 1%2B+12%2F5 = 17%2F5

Points of solution would be (2,-3) and (++%28-6%29%2F5, 17%2F5 ).

Check for errors in my work!! Let me know if I made any.

R^2 at SCC


Polynomials-and-rational-expressions/12380: no matter what i do, i can't figure this 1 out, please help 3y(2y-3)(3y-4)=0
1 solutions

Answer 6290 by rapaljer(4667) About Me  on 2005-09-23 16:39:59 (Show Source):
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You have a product equal to zero:

3y(2y-3)(3y-4)=0

If a product of numbers equals to zero, then one of those numbers must be zero. Because this can be thought of as a product of three quantities, you can make three separate solutions:

Solution #1.
3y = 0
y=0

Solution #2:
2y-3 = 0
2y= 3
y+=+3%2F2

Solution #3:
3y-4=0
3y = 4
y+=+4%2F3

R^2 at SCC


Percentage-and-ratio-word-problems/12363: Please help me I need this by Monday, please!! :0)
An investment of $1500 paid interest of $45 during a certain period. How much interest would an investment of $2000 invested at the same rate for the same length of time pay?
1 solutions

Answer 6289 by rapaljer(4667) About Me  on 2005-09-23 16:35:08 (Show Source):
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Since the Interest paid is in proportion to the Investment, you can set up a proportion:

Let x = interest earned on a $2000 investment.
+%28Interest%29%2F+%28Investment%29= +45%2F1500+=+x%2F2000

Remember a%2Fb=c%2Fd means ad=bc

In the same way,
45%2F1500+=+x%2F2000+ means 45%2A2000=+x%2A1500

x=+%2845%2A2000%29%2F1500
x=+60+

An easier way to look at it, since $2000 is actually $1500 plus one third of that amount, the interest earned will be the corresponding $45 plus one third of that amount, or $45 + 15 = $60.

R^2 at SCC


Probability-and-statistics/12361: How many arrangements of the letters in the word olive can you make if each arrangement must use three letters?

1 solutions

Answer 6288 by rapaljer(4667) About Me  on 2005-09-23 14:18:53 (Show Source):
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The key word is "arrangement" which means that the order is significant. This makes the problem a PERMUTATION, a permutation of the 5 letters in the word OLIVE taken 3 at a time. There are a lot of notations that can be used here, one of which, the easiest to type here, is P(5,3). It means to start with the first number 5, and start counting down. You must have THREE numbers (that is the second number), in the product:

P(5,3) = 5*4*3 = 60 different arrangements.

R^2 at SCC



Exponential-and-logarithmic-functions/12356: im using substitution in algera2 and i cant figure this one out
{4x - y = 22
{ 2x + 3y = 4
1 solutions

Answer 6283 by rapaljer(4667) About Me  on 2005-09-23 12:12:53 (Show Source):
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Solve for y in the first equation:
4x - y = 22
4x-4x - y = 22- 4x
-y = -4x + 22
y = 4x - 22

Substitute into the second equation:
2x + 3y = 4
2x + 3(_____)=4
2x + 3(4x-22) = 4
2x + 12x - 66 = 4
14x =70
x=5

Substitute back into first equation to solve for y:
y=4x -22
y=4*5 - 22
y=20-22
y=-2

Check in the second equation:
2x + 3y = 4
2(5)+3(-2) = 4
10-6= 4
It checks.

R^2 at SCC


Equations/12345: 5d+9-4d=51-5d
1 solutions

Answer 6282 by rapaljer(4667) About Me  on 2005-09-23 12:00:57 (Show Source):
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5d+9-4d=51-5d
d +9 = 51 - 5d

Add 5d to each side:
d + 5d + 9 = 51 - 5d + 5d
6d + 9 = 51

Subtract 9 from each side:
6d + 9 - 9 = 51 - 9
6d = 42
d= 7

R^2 at SCC
d= 7