№22
15х+10=7+12у
15х+3=12у
5х+1=4у
у=(5х+1)/4 х= (4у-1)/5
4х+4у+х=31
5х+4у=31
у=(31-5х)/4 х=(31-4у)/5
№24
2х+4у-7у=6
2х-3у=6
х=(6+3у)/2 у= - (6-2х)/3
10х+5у-х=2х+60
7х+5у=60
х= (60-5у)/7 у=(60-7х)/5
№22
15х+10=7+12у
15х+3=12у
5х+1=4у
у=(5х+1)/4 х= (4у-1)/5
4х+4у+х=31
5х+4у=31
у=(31-5х)/4 х=(31-4у)/5
№24
2х+4у-7у=6
2х-3у=6
х=(6+3у)/2 у= - (6-2х)/3
10х+5у-х=2х+60
7х+5у=60
х= (60-5у)/7 у=(60-7х)/5