SOLUTION: How do I solve this system of equations by using multiplication with the addition method? 1/5(x+2y)=-2 x/4-3y/2=15/2

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Question 140983This question is from textbook Prentice Hall Algebra 1
: How do I solve this system of equations by using multiplication with the addition method?
1/5(x+2y)=-2
x/4-3y/2=15/2 This question is from textbook Prentice Hall Algebra 1

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
How do I solve this system of equations by using multiplication with the addition method?
:
1/5(x+2y) = -2
Multiply by 5 to get rid of the denominator
x + 2y = 5(-2)
x + 2y = -10
:
x%2F4 - %283y%29%2F2 = 15%2F2
Multiply equation by 4 to get rid of the denominator, resulting:
x - 2(3y) = 2(15)
x - 6y = 30
:
Multiply the 1st equation by -1 and add to the above equation
-x - 2y = +10
+x - 6y = +30
-----------------
0x - 8y = +40
y = 40%2F%28-8%29
y = -5
:
Find x using x - 6y = 30:
x - 6(-5) = 30
x + 30 = 30
x = 0
;
:
Check solution using the 1st original equation:
1/5(x + 2y) = -2
1/5(0 + 2(-5) =
1/5 * -10 = -2