5,04:(104,2-х)=1,2
1,2х+4,5х-0,7=1.01

5,04:(104,2-х)=1,25.04/1,2=104,2-х4,2=104,2-хх=104,2-4,2х=1001,2х+4,5х-0,7=1.015,7х=1,01+0,75,7х=1,71х=0,3

Скачай wolfram alpha!!!!!!!!!