2х=-26+10

2х=-16

х=-16:2

х=-8

7у=40+9

7у=49

у=49:7

у=7

-15у=23-8

-15у=15

у=15:(-15)

у=-1

1) =х+х=10-26=-16

2)=10y-3y=40-9=4.428

3) =-y-14y=23-8= 15y=15=-1