What is-2x+6y=6 7x+8y=-6?

We can solve this by substitution

-2x=6-6y

-2x/-2 = (6-6y) / - 2

x = - 3+3y

7 (-3+3y) + 8y=-6

-21+21y+8y=-6

29y=15

y=15/29

-2x+6 (15/29) = 6

-2x+90/29=6

-2x=6-90/29

-2x = 174/29-90/29

-2x = 84/29

-2x (29) = (84/29) 29

-54x=84

x = - 84/54

x = - 14/9

so x = - 14/9

y = 15/29