Question 464287
a + b = 180 ------> -a - b = -180 {multiplied top equation by -1}
a - 2b = 30


-a - b = -180 {new top equation}
a - 2b = 30 {original bottom equation}
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-3b = -150 {added the two equations together}
b = 50 {divided both sides by -3}


a + b = 180 {original top equation}
a + 50 = 180 {substituted 50, in for b, into top equation}
a = 130 {subtracted 50 from both sides}


a = 130 and b = 50
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