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Complex_Numbers/736466: 1. x^4 + 3x^2 - 4 =0
1 solutions

Answer 449867 by sofiyac(695) on 2013-04-11 12:19:29 (Show Source):

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Make sure you include instructions with your problem on what it asks you to do so we don't have to guess.
x^4 + 3x^2 - 4 =0
(x^2 + 4)(x^2 - 1) =0
(x^2 + 4)(x+1)(x-1) =0
x^2 + 4=0 or x+1 =0 or x-1=0
x^2 = -4 or x+1 =0 or x-1=0 solve for x
x=2i or x=-1 or x=1

Age_Word_Problems/736499: Tom is five times as old as his little brother Ben. Together, the some of their ages are 42. How old is each?

1 solutions

Answer 449866 by sofiyac(695) on 2013-04-11 12:11:08 (Show Source):

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Let ben be x years old
then Tom would be 5x years old
Add their ages and make sum equal to 42
x+5x=42 solve for x
6x=42 divide each side by 6
x=7
so ben is 7 years old and tom is 5*7=35 years old

test/736476: Factor by grouping 5x^2-20x+2x-8
1 solutions

Answer 449865 by sofiyac(695) on 2013-04-11 12:09:00 (Show Source):

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5x%5E2-20x%2B2x-8

percentage/736482: What is 10% off of $7.35?
1 solutions

Answer 449864 by sofiyac(695) on 2013-04-11 12:06:09 (Show Source):

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divide 7.35 by 10 or simply move the decimal point to the left by one spot, either way the answer is 0.735

Travel_Word_Problems/736497: I have to drive the distance of 428 miles. My gas tank holds 18 gallons of gas. I pay $3.99 per gallon of gas. How much will the gas cost me to drive the 428 miles.
1 solutions

Answer 449863 by sofiyac(695) on 2013-04-11 12:03:28 (Show Source):

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I don't think there's enough information to solve this problem, we need to know how many miles you can drive per gallon.

Miscellaneous_Word_Problems/736486: A store sells tents, sleeping bags, and camp stools. A customer buys a tent, 2 sleeping bags, and 5 camping stools for $220. The price of the tent is 7 times the cost of a camp stool. The cost of a sleeping bag is $40 more than the cost of a camp stool. Find the cost of each item.
1 solutions

Answer 449861 by sofiyac(695) on 2013-04-11 11:59:58 (Show Source):

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let
camp stools cost x dollars then
tent would cost 7x dollars and
sleeping bag cost would be x+40
A customer buys a tent, 2 sleeping bags, and 5 camping stools for $220, so now we plug in the above defined cost into this sentence to make equation out of it.
one tent would cost 1*7x
2 sleeping bags would cost 2(x+40)
5 camping stools would cost 5x
Next we add them all up and make the sum equal to 220
7x+2(x+40)+5x=220 now we solve for x
7x+2x+80+5x=220
14x=140 divide both sides by 14
x=10 now go back all the way to the top where we defined how much everything cost and plug in 10 where you see x
camp stools cost x dollars so camp stools cost $10
tent would cost 7x dollars so tent costs 7*10=$70
sleeping bag cost would be x+40 so sleeping bag cost is 10+40=$50

Numeric_Fractions/729161: x to the second power plus 6x= negative8

1 solutions

Answer 445761 by sofiyac(695) on 2013-03-21 19:40:58 (Show Source):

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x^2+6x=-8
x^2+6x+8=0
(x+4)(x+2)=0
x=-4 or x=-2

Equations/729174: n= 9, e= 18 and l= -54
Evaluate the algebraic expression
n*(e+1)/9
1 solutions

Answer 445760 by sofiyac(695) on 2013-03-21 19:39:18 (Show Source):

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n= 9, e= 18 and l= -54
Evaluate the algebraic expression
%289%2A%2818-54%29%29%2F9=%289%2A%28-36%29%29%2F9=-36

Linear-equations/729185: how to graph y=x+5

1 solutions

Answer 445759 by sofiyac(695) on 2013-03-21 19:37:03 (Show Source):

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plug in x any number for x, solve for y
x=0 then y=5 so first point (0,5)
then plug in different number for x and find different y, so lets try
x=2 then y=7 so second point would be (2,7)
plot both points and connect the dots
+graph%28+300%2C+300%2C+-6%2C+6%2C+-6%2C+6%2C+x%2B5%29+

+graph%28+300%2C+300%2C+-6%2C+6%2C+-6%2C+6%2C+x%2B5%29+

Quadratic_Equations/729183: 4(x+9)^2=24
1 solutions

Answer 445755 by sofiyac(695) on 2013-03-21 19:33:50 (Show Source):

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4%28x%2B9%29%5E2=24+

divide both sides by 4
%28x%2B9%29%5E2=6

subract 6 from each side of the equal side
x%5E2%2B18x%2B75=0

now you can use the quadratic formula to solve for x
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-18+%2B-+sqrt%28+18%5E2-4%2A1%2A75+%29%29%2F%282%2A1%29+

x+=+%28-18+%2B-+sqrt%28+324-300+%29%29%2F%282%29+

x+=+%28-18+%2B-+sqrt%28+24+%29%29%2F%282%29+

simplify sqrt(24)
x+=+%28-18+%2B-+2sqrt%28+6+%29%29%2F%282%29+

divide everything by 2
x+=+%28-9+%2B-+sqrt%28+6+%29%29+

Numeric_Fractions/729186: How do you rename a mixed number in simplest form. what would the simplest form of 9%265%2F3

be?
1 solutions

Answer 445754 by sofiyac(695) on 2013-03-21 19:32:37 (Show Source):

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9+%285%2F3%29=%289%2A3%2B5%29%2F3=32%2F3

to rename you take whole number (9) multiply by bottom number (3) and add top number (5) = your new top. The bottom remains the same (3).

Quadratic_Equations/729189: Please help me solve this quadratic: 4(x+9)^2=24
What I've tried doing:
4(x+9)^2=24
4x+36^2=24
4x+1296=24
4x+1272=0
I am not sure what to do from here.
I have also decided that it cannot be factored evenly.
1 solutions

Answer 445752 by sofiyac(695) on 2013-03-21 19:29:26 (Show Source):

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4%28x%2B9%29%5E2=24+

divide both sides by 4
%28x%2B9%29%5E2=6

subract 6 from each side of the equal side
x%5E2%2B18x%2B75=0

now you can use the quadratic formula to solve for x
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

simplify sqrt(24)
x+=+%28-18+%2B-+2sqrt%28+6+%29%29%2F%282%29+

divide everything by 2
x+=+%28-9+%2B-+sqrt%28+6+%29%29+

Linear-systems/702135: Please help me with Algebra 1
Mid chapter Quiz
Page 212
number 13-15
It's said Suppose you have already saved $75 toward the cost of a new television.
You plan to save $5 more each week for the next several weeks.
13. Write an equation for the total amount T you will have w weeks from now.
14. Graph the equation.
15. Find the total amount saved after 10 weeks.

1 solutions

Answer 432822 by sofiyac(695) on 2013-01-14 20:28:12 (Show Source):

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13.T=75+5w
15.T=75+5*10
T=75+50
T=125
14.
+graph%28+300%2C+200%2C+-100%2C+100%2C+-100%2C+100%2C+75%2B5x%29+

test/702143:
1 solutions

Answer 432821 by sofiyac(695) on 2013-01-14 20:25:00 (Show Source):

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test/702142:
1 solutions

Answer 432820 by sofiyac(695) on 2013-01-14 20:24:44 (Show Source):

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Travel_Word_Problems/702139: Gas mileage of a car when traveling 5522 km using 11 gallons of gas
1 solutions

Answer 432819 by sofiyac(695) on 2013-01-14 20:22:18 (Show Source):

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5522/11=502 gallons per km

Travel_Word_Problems/702141: how far, in meters, will a car travel in 20 seconds at an average speed of 20m/s?
1 solutions

Answer 432818 by sofiyac(695) on 2013-01-14 20:21:18 (Show Source):

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20*20=400 meters

Expressions-with-variables/702133: which of the following expressions is equivalent to 20-4/5x greater or equal to 16?
A. x is greater than or equal to 5
B. x is less than or equal to 5
C. x is greater or equal to 32 1/2
D. x is less than or equal to 32 1/2
Can you please explain why? Thank You
1 solutions

Answer 432816 by sofiyac(695) on 2013-01-14 20:20:42 (Show Source):

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20-4/5x>=16 solve it for x, that will tell you why
-4/5x>=-4 we flip the sign because we multiplied both sides by negative 5/4
x<=5 so answer is B

Expressions-with-variables/702132: which of the following expressions is equivalent to 20-4/5x greater or equal to 16?
A. x is greater than or equal to 5
B. x is less than or equal to 5
C. x is greater or equal to 32 1/2
D. x is less than or equal to 32 1/2
1 solutions

Answer 432815 by sofiyac(695) on 2013-01-14 20:20:14 (Show Source):

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20-4/5x>=16 solve it for x, that will tell you why
-4/5x>=-4 we flip the sign because we multiplied both sides by negative 5/4
x<=5 so answer is B

Quadratic_Equations/702137: 3a2b-3ab find ab-c

1 solutions

Answer 432812 by sofiyac(695) on 2013-01-14 20:18:00 (Show Source):

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there's no c in your equation, repost the problem

Exponents/702031: (.5y)^2 (2y)^5
1 solutions

Answer 432811 by sofiyac(695) on 2013-01-14 20:16:12 (Show Source):

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0.25y^2*32y^5=8y^7

Equations/702127: solve for the equation for x:y= mx + b
1 solutions

Answer 432809 by sofiyac(695) on 2013-01-14 20:09:10 (Show Source):

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mx=b-y
x=(b-y)/m

Linear-equations/702126: Find x : 3x=1
1 solutions

Answer 432808 by sofiyac(695) on 2013-01-14 20:08:29 (Show Source):

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divide both sides by 3
x=1%2F3

Geometry_proofs/702130: a proof for theorem 6-4
1 solutions

Answer 432807 by sofiyac(695) on 2013-01-14 20:07:48 (Show Source):

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we don't have your book so we don't know what 6.4 is, post the whole problem

Inverses/702122: 2(y-3)=4y+6
1 solutions

Answer 432806 by sofiyac(695) on 2013-01-14 20:01:10 (Show Source):

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2y-6=4y+6
-12=2y
-6=y

Average/702118: Find values for x and y that fit both of the equations 5x+3y = 8 and 4x + 3y = -2.
1 solutions

Answer 432805 by sofiyac(695) on 2013-01-14 20:00:17 (Show Source):

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5x+3y = 8
4x+3y = -2 multiply this one by -1
***
5x+3y = 8
-4x-3y=-2 add the two equations
***
x=6 now plug that into either of the originals and solve for y, i'll use first one
5*6+3y=8
3y=-22
y=-22/3
(6,-22/3)

Linear-equations/702120: For which 5-years time period was rate of change the greatest? the least?
1 solutions

Answer 432802 by sofiyac(695) on 2013-01-14 19:57:37 (Show Source):

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we need to see a graph for this one

Sequences-and-series/702117: The question is: eight subtracted from six times a number is 298. Find the number. Thank you!
~Kelly
1 solutions

Answer 432801 by sofiyac(695) on 2013-01-14 19:56:38 (Show Source):

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6x-8=298
6x=306
x=51

test/702027: 3·+2[3·+3]=6
1 solutions

Answer 432800 by sofiyac(695) on 2013-01-14 19:55:24 (Show Source):

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i can't tell what the little dots are in front of the plus side, please re submit the problem and copy correctly

test/702115:
1 solutions

Answer 432798 by sofiyac(695) on 2013-01-14 19:54:22 (Show Source):

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test

test/702028: -4x+2y=-20
-7x+8y=-8
1 solutions

Answer 432797 by sofiyac(695) on 2013-01-14 19:53:42 (Show Source):

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-4x+2y=-20 multiply this one by -4
-7x+8y=-8
***
16x-8y=80
-7x+8y=-8 now add them
***
9x=72 divide both sides by 9
x=8 now plug this into either of the original equations, i'll use first one
-4(8)+2y=-20
-32+2y=-20 add 32 to each side
2y=12 divide both sides by 2
y=6
(8,6)

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