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sofiyac answered: 695 problems
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Linear-equations/474547: Solve using the elimination method.
-5x - 7y = 25.5
-2x + 10y = -9
1 solutions

Answer 325435 by sofiyac(695) on 2011-07-26 12:24:07 (Show Source):

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-5x - 7y = 25.5 multiply first one by 2, second one by -5 and add them
-2x + 10y = -9
***
-10x-14y=51
10x-50y=45
------------
-64y=96 divide each side by -64
y=-1.5 plug it into one of the original equations and solve for x
-2x + 10y = -9
-2x + 10*(-1.5) = -9
-2x-15=-9
-2x=6 divide each side by -2
x=-3
solution is (-3,-1.5)

Polynomials-and-rational-expressions/474548: Factor the following expression into a product of two binomials 121x^2-132x+36
1 solutions

Answer 325434 by sofiyac(695) on 2011-07-26 12:20:35 (Show Source):

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121x%5E2-132x%2B36=%2811x-6%29%2811x-6%29

Polynomials-and-rational-expressions/474549: Completely factor the following expression 25a^2-60ab+36b^2
1 solutions

Answer 325433 by sofiyac(695) on 2011-07-26 12:19:37 (Show Source):

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25a%5E2-60ab%2B36b%5E2=%285a-6b%29%5E2

Inequalities/473079: 12. Solve this compound inequality, showing all work. Graph the solution on the number line and express the answer using interval notation.
X
Y1
Y2
-3
-2
8
-2
0
5
-1
2
2
0
4
-1
1
6
-4
2
8
-7
3
10
-10
3v+7≤2v+5 or 4v+1≤6v-5
−4 −3 −2 −1 0 1 2 3 4 5
Interval Notation: __________________
1 solutions

Answer 324413 by sofiyac(695) on 2011-07-22 13:12:15 (Show Source):

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3v%2B7%3C=2v%2B5

(-infinity, -2] or [3, +infinity)

Rectangles/473107: A rectangle has an area of 48 square feet and a perimeter of 32 feet. Which of the following could be its dimensions?
1 solutions

Answer 324412 by sofiyac(695) on 2011-07-22 13:07:08 (Show Source):

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you didn't list the options
xy=48
2x+2y=38
solve for x and y

Rectangles/473123: The length of a table is 3 m greater than the width. The area is 70 m^2. Find the dimensions of the table
1 solutions

Answer 324410 by sofiyac(695) on 2011-07-22 13:06:05 (Show Source):

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width is x
length is x+3
area=length*width
70=x(x+3)
70=x^2+3x
0=x^2+3x-70
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-3+%2B-+sqrt%28+9%2B280+%29%29%2F%282%29+

measure can't be negative for length and width so we have to go with + option
x+=+%28-3+%2B+17%29%2F2+

so width is 7, then length is 7+3=10

Travel_Word_Problems/473124: Driving at 42 mph one covers 19 miles in?
1 solutions

Answer 324407 by sofiyac(695) on 2011-07-22 13:02:13 (Show Source):

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distance=rate*time
time=distance/rate
time=19/42=0.45 hours
about half hour

test/471569: Graph function f by starting with y=x^2
f(x)= -x^2-10
1 solutions

Answer 323435 by sofiyac(695) on 2011-07-18 16:34:37 (Show Source):

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x%5E2

+graph%28+200%2C+200%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E2%29+

+graph%28+200%2C+200%2C+-10%2C+10%2C+-20%2C+1%2C+-x%5E2-10%29+

Complex_Numbers/470082: +x+%2B+sqrt%28x%29+-+20+=+0+

1 solutions

Answer 322887 by sofiyac(695) on 2011-07-15 16:21:56 (Show Source):

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+x+%2B+sqrt%28x%29+-+20+=+0+

x+=+%2841+%2B-+sqrt%28+1681-1600+%29%29%2F%282%29+

x+=+%2841+%2B-+sqrt%28+81+%29%29%2F%282%29+

Length-and-distance/469786: Find EF.
1 solutions

Answer 322884 by sofiyac(695) on 2011-07-15 16:16:03 (Show Source):

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That's not enough information

Polynomials-and-rational-expressions/470157: I am taking math 4106-1 Factoring and algebraic fractions and I am soooo lost i get some of the formulas but just done know when to use them Please help me!
1 solutions

Answer 322883 by sofiyac(695) on 2011-07-15 16:15:11 (Show Source):

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you have to post the problem that you would like help with, or i can tutor you privately if you'd like to pay via paypal, thanks

test/469772: Find (f•g)(x) and (g•
1 solutions

Answer 322882 by sofiyac(695) on 2011-07-15 16:14:02 (Show Source):

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directions aren't finished

Evaluation_Word_Problems/469747: Hi please help with this equation...
Solve for X
1.)X(exponent 2)-3X-10=0
1 solutions

Answer 322881 by sofiyac(695) on 2011-07-15 16:12:43 (Show Source):

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x%5E2-3x-10=0

a=1
b=-3
c=-10
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%283+%2B-+sqrt%28+9%2B40%29%29%2F%282%29+

x+=+%283+%2B-+sqrt%28+49%29%29%2F%282%29+

Probability-and-statistics/469730:
1 solutions

Answer 322879 by sofiyac(695) on 2011-07-15 16:08:53 (Show Source):

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nothing posted

Linear-equations/469738: determine the slope of the line passing through each pair of points.
1. (1,4) (2,7)
2. (-2,4) (5,-10)
3. (-3,6) (-3,8)
4 (-4,6) (-6,-1)
1 solutions

Answer 322878 by sofiyac(695) on 2011-07-15 16:08:27 (Show Source):

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1. (1,4) (2,7)
m=%28y2-y1%29%2F%28x2-x1%29=%287-4%29%2F%282-1%29=3%2F1=3

so the slope is 3
use the same formula for the rest of the points, same steps just different numbers

Quadratic_Equations/469744: 1. y>-2+3
2.2x-2y less than 6
3.-y<-x
4. x more than 5
4x+3y more than 6
1 solutions

Answer 322877 by sofiyac(695) on 2011-07-15 16:06:50 (Show Source):

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1. y>-2+3
y>1
2.2x-2y less than 6 (not sure what we're supposed to do here)
2x-2y<6
3.-y<-x
y>x this would be the simplified version
4. x more than 5
x>5
4x+3y more than 6
4x+3y>6

Graphs/470701: graph the soultion set:
4x+5y>10
1 solutions

Answer 322876 by sofiyac(695) on 2011-07-15 16:02:36 (Show Source):

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4x+5y>10
5y>10-4x
y>2-(4x/5)
shade the line UP and the line will be DOTTED not solid
+graph%28+200%2C+200%2C+-5%2C+5%2C+-5%2C+5%2C+2-%284x%2F5%29%29+

+graph%28+200%2C+200%2C+-5%2C+5%2C+-5%2C+5%2C+2-%284x%2F5%29%29+

Equations/470491: 5+m\7=10
1 solutions

Answer 322848 by sofiyac(695) on 2011-07-15 13:53:05 (Show Source):

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m/7=5
m=35

test/470466: Find the product: 4x(x2 + 5x – 7)

a. 4x3 + 20x2 – 28x
b. 5x3 + 9x2 – 3x
c. 4x2 + 20x – 28
d. 4x3 + 5x –7

1 solutions

Answer 322847 by sofiyac(695) on 2011-07-15 13:48:12 (Show Source):

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a)

Probability-and-statistics/470440: why would you keep outliers in an data entry about high temperatures?
1 solutions

Answer 322846 by sofiyac(695) on 2011-07-15 13:46:00 (Show Source):

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you want to know whta the record temperatures were

Graphs/470674: A straight line passes through the points (2,2) and (0,2).
If we want to express the line equation in the form Ax-C=By
Find the values of A,B and C.

1 solutions

Answer 322845 by sofiyac(695) on 2011-07-15 13:44:49 (Show Source):

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m=%28y2-y1%29%2F%28x2-x1%29=%282-2%29%2F%280-2%29=0

y-y1=m(x-x1) plug in your m and one of the points, doesn't matter which
y-2=0(x-0)
y-2=0
y=2
i think you copied wrong
it's ax+by=c
so a=0
b=1
c=2

Exponential-and-logarithmic-functions/470412: Solve the system by the addition or substitution method.
x - 6y = -46
-3x - 7y = -62
1 solutions

Answer 322842 by sofiyac(695) on 2011-07-15 13:40:42 (Show Source):

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x - 6y = -46
-3x - 7y = -62 multiply first one by 3 and add to second one
***
3x - 18y = -138
-3x - 7y = -62 add them
************
-25y=-200 divide each side by -25
y=8
plug into either of the equations
x-6*8=-46
x-48=-46
x=2
(2,8)

Inequalities/470671: Solve the inequality, graph the solution set on the real number line, and then write the solution in interval notation.
+%28x-5%29%2F%28x%2B1%29+%3C+%28x%2B2%29%2F%28x-3%29+

+%28x-5%29%2F%28x%2B1%29+%3C+%28x%2B2%29%2F%28x-3%29+

1 solutions

Answer 322841 by sofiyac(695) on 2011-07-15 13:30:38 (Show Source):

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(thanks for writing it correctly)
cross multiply
+%28x-5%29%28x-3%29+%3C+%28x%2B1%29%28x%2B2%29+

+%28x%5E2-8x%2B15%29+%3C+%28x%5E2%2B3x%2B2%29+

move x's to one side everything else to the other
+%2813%29+%3C+%2811x%29+

divide both sides by 11
+%2813%2F11%29+%3C+x+

Geometry_Word_Problems/470670: I am not sure how to set the problem up i keep tryingg but i cant get the right anwser. Im also not sure how to convert the feet to miles
How many hours will it take a bicyclist travling at 17.6 feet per second to finish a 90 mile race?
1 solutions

Answer 322840 by sofiyac(695) on 2011-07-15 13:26:55 (Show Source):

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1 miles = 5280 feet
1 hour = 3600 seconds
+%2817.6feet%2F1+second%29%281+mile%2F5280feet%29%283600seconds%2F1hour%29=12miles%2Fhour

+%2817.6feet%2F1+second%29%281+mile%2F5280feet%29%283600seconds%2F1hour%29=12miles%2Fhour

90/12=7.5 hours

Numbers_Word_Problems/470622: The sum of two consecutive numbers is 6 more than three times their difference. find the two numbers
1 solutions

Answer 322839 by sofiyac(695) on 2011-07-15 13:21:45 (Show Source):

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first number x, second one x+1
x+x+1-6=3(x+1-x)
2x-5=3
2x=8
x=4
so first one is 4 second one is 4+1=5

Percentage-and-ratio-word-problems/470604: In 2004, 41.2 million people
were enrolled in Medicare, an increase of 5.1% from
2000. How many people were enrolled in Medicare in
2000?

1 solutions

Answer 322837 by sofiyac(695) on 2011-07-15 13:19:36 (Show Source):

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In 2004, 41.2 million people
were enrolled in Medicare, an increase of 5.1% from
2000. How many people were enrolled in Medicare in
2000?
percent million
105.1----41.2
100--------x
so 105.1 percent would be 41.2 and 100 percent would be x, cross multiply and solve for x
105.1x=4120
x=39.2 million

Rectangles/470666: the perimeter of a rectangle is 40ft. The ratio of the width to length is 2:3. How do you find the length and the width?
1 solutions

Answer 322835 by sofiyac(695) on 2011-07-15 13:16:42 (Show Source):

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2x+2y=40
x%2Fy=2%2F3

10y=120
y=12
x=2y%2F3=2%2A12%2F3=24%2F3=8

so the sides are 12 and 8

Equations/470668: How do I simplify this equation by factoring?
Here is the link to the image, as I don't know how to type it out.
http://www.flickr.com/photos/53982956@N07/5940260063/
1 solutions

Answer 322834 by sofiyac(695) on 2011-07-15 13:10:27 (Show Source):

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the image doesn't come up

expressions/470585: What is the algebraic expresesion for these three question the quoitent of the square of a number t and 14 and the product of 6 and the quanity 2 more than a number x is at least 45 and three times the sum of 4 and number y squared is the same as differnece of 14 and the number y
1 solutions

Answer 322832 by sofiyac(695) on 2011-07-15 13:09:04 (Show Source):

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can't tell where the first question ends and second begins, repost all separately, thanks

Probability-and-statistics/470565: a final exam in statistics course has a mean of 84 and a standanrd deviation of 4 find the corresponding z-score for each raw score a.99 b.76 c.80

1 solutions

Answer 322831 by sofiyac(695) on 2011-07-15 13:07:19 (Show Source):

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Graphs/470564: Graph the function below by using its exponential form.
f(x)=log1.2^x

1 solutions

Answer 322830 by sofiyac(695) on 2011-07-15 13:06:38 (Show Source):

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we can't graph using logs on this website

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