Question

解方程：x=2乘[.25(x-10)-10] 6.7-0.8x=3(1.7-0.2x) 28+1.9x=4(6+0.6x

Answer 1

x=2*[1.25(x-10)-10]

x=2*[1.25x-22.5]

x=2.5x-45

1.5x=45

x=30

6.7-0.8x=3(1.7-0.2x)

6.7-0.8x=5.1-0.6x

1.6=0.2x

x=8

28+1.9x=4(6+0.6x)

28+1.9x=24+2.4x

4=0.5x

x=8

x-4=2*[1.5(x-4)-24]

x-4=2*(1.5x-6-24)

x-4=3x-60

56=2x

x=28