1、式子2(x+3)与2.5(x-3)的值互为相反数,求x的值。
2、解方程:
2(1-5x)=5-2(x-1.5)
1 2(x+3)+2.5(x-3)=0
2 2-10x=5-2x+3 8x=-6
2(X+3)+2.5(x-3)=0 x=1/3
2-10x=5-2x+3 x= - 3/4