2(12-x)+4x=42
问题描述:
2(12-x)+4x=42
4x-2(30-x)=24
答
1.24-2x+4x=42
2x+24=42
2x=42-24
2x=18
x=9
2.4x-60+2x=24
6x=24+60
6x=84
x=14