Question

用代入消元法解这个方程2x+9y=134/3(x-1)-y=1/3

Answer 1

4/3(x-1)-y=1/3

y=4/3(x-1)-1/3=4/3x-5/3

带入到2x+9y=13得

2x+12x-15=13

14x=28

x=2

则y=4/3*2-5/3=1