Question

metodo de sustitucion
2x+3y=7

5x-y=9

Answer 1

5x-y=9......(1) ------> 5x-9=y
2x+3y=7....(2)

 2x+3(5x-9)=7...(2)           5(2)-y=9......(1)
2x+15x-27=7                   y=1
17x=34
x=2