Answer:
Explanation:
x + y = 169
y = x + 7
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Substitute for y in the first equation
x + x+7 =169
2x + 7 = 169 Subtract 7 from both sides
2x+7-7 = 169 - 7
2x = 162 Divide by 2
2x/2 = 162/2
x = 81
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solve for y
y = x + 7
y = 81 + 7
y = 88