SOLUTION: Solve each equation by using substitution a+b=20 a-b=-4

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Question 795297: Solve each equation by using substitution
a+b=20
a-b=-4
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
a+b=20......1
a-b=-4......2
Convert Eq(2)
a - b = - 4
a = -4 + b
Substitute into Eq(1)
a + b = 20
-4 + b + b = 20
2b = 20 + 4
2b = 24
b = 12
Substitute b = 12
into Eq (1)
a + b = 20
a + 12 = 20
a = 20 - 12
a = 8.
Hope this helps.
;-)