Question

how do you use the elemination method to solve x+y=9 , x-y=7

Answer 1

add the 2 equations together

x+y =9

x-y =7

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2x = 16

divide by 2

x=8

x+y =9

substitute in x=8

8+y =9

subtract 8 from each side

y =1

(8,1)