Question

y=20-x代入2x+y=38中的y得2x+()=38

Answer 1

y=20-x代入2x+y=38

2x+20-x=38

x=18

y=2

x=3+y代入3x-8y=14得

3(3+y)-8y=14

9+3y-8y=14

9-5y=14

-5y=5

y=-1

x=2