解方程:x*(1+40%)*80%=x+30 5000+5000*3*x*(1-5%)=5285 8x+3=7x-4

问题描述:

解方程:x*(1+40%)*80%=x+30 5000+5000*3*x*(1-5%)=5285 8x+3=7x-4

解方程:
x*(1+40%)*80%=x+30
1.4x*0.8=x+30
1.12x=x+30
0.12x=30
x=250

5000+5000*3*x*(1-5%)=5285
5000+15000x*0.95=5285
5000+14250x=285
14250x=285
x=0.02
x=2%

8x+3=7x-4
8x-7x=-4-3
x=-7