1/6[20x+50]+2/3[5+2x]-1/2[4x+10]=0

问题描述:

1/6[20x+50]+2/3[5+2x]-1/2[4x+10]=0

1/6[20x+50]+2/3[5+2x]-1/2[4x+10]=0
10/3x+25/3+10/3+4/3x-2x-5=0
8/3x+20/3=0
8/3x= -20/3
x= -20/8
x= -5/2
x=-2.5

原式=2(3x -4x +5x-6)-7(3x -5x-7)+10(-3x +2x -4x-当x=-1/6时原式=-24×(-1/6) -9×(-1/6) +5×(-1/6)-13

1/6[20x+50]+2/3[5+2x]-1/2[4x+10]=0
两边同时乘以6
20x+50+4(5+2x)-3(4x+10)=0
20x+50+20+8x-12x-30=0
16x=-40
x=-2.5