Question

Решите 2 уравнение: 1)87100: (870+х)=100 2)3*(0,2х-5)-4*(0,3-5)=10+0,4х ответы: 1)1 2)31

Answer 1

$1)87100:(870+x)=100 \\ 870+x=87100:100 \\ 870+x=871 \\ x=871-870 \\ x=1$

$2)3*(0.2x-5)-4*(0.3-5)=10+0.4x \\ 0.6x-15-4*(-4.7)=10+0.4x \\ 0.6x-15+18.8=10+0.4x \\ 0.6x-0.4x=10+15-18.8 \\ 0.2x=6.2\\x=6.2:0.2\\x=31$