Question

20(10-x)-200(9-x)=2000

Answer 1

20(10-х)-200(9-х)=2000
20(19-2х)-200=2000
20(19-2х)=2000-200
20(19-2х)=1800
19-2х=1800÷20
19-2х=90
2х=19+90
2х=109
х=109÷2
х=54,5