3a+2b=15 5b-2a=123 求a等于几,b等于几?
问题描述:
3a+2b=15 5b-2a=123 求a等于几,b等于几?
答
4b+6a=30 15b-6a=369 两式相加得b=21 代入得a=-9
3a+2b=15 5b-2a=123 求a等于几,b等于几?
4b+6a=30 15b-6a=369 两式相加得b=21 代入得a=-9