SOLUTION: solve each system using the substution method. 2x+2y=7 and 4x+3y=-1

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Question 176085: solve each system using the substution method. 2x+2y=7 and 4x+3y=-1
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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solve each system using the substution method.
2x + 2y = 7
2y = 7 - 2x
y = 7%2F2 - 2%2F2x
y = 3.5 - x
:
and
4x + 3y = -1
:
Substitute (3.5-x) for y in the above equation
4x + 3(3.5-x) = -1
4x + 10.5 - 3x = -1
4x - 3x = -1 - 10.5
x = -11.5
:
Find y, substitute -11.5 for x in the 1st original equation
2(-11.5) + 2y = 7
-23 + 2y = 7
2y = 7 + 23
2y = 30
y = +15
:
:
Check solutions in the 2nd original equation:
4(-11.5) + 3(15) = -1
-46 + 45 = -1