Math problem!!!!!

Question

Solve the system of linear equations by elimination.

x+y=2

2x+7y=9

Answer 1

multiply 1st equation by 2 and subtract it from 2nd equation, eliminating x

2x+7y=9

2x+2y=4

5y = 5

y =1

x=2-y = 2-1=1

x=1