Solve for y.

7 + y = -6 ?

solve step-by-step using rules of algebra:

(problem) 7 + y = -6 -->
(subtract 7 from BOTH sides) 7 + y - 7 = -6 - 7 -->
(collect like terms - in this case, constants) y + (7 - 7) = (-6-7) -->
(reduce) y + 0 = -13
(reduce) y = -13 (answer)

Elimination Method

2x – y = - 9
x + y = 6

Add the two equations to eliminate y.

(2x + x) + (- y +y) = - 9 + 6

3x + 0 = -3

3x = - 3

x = - 1

To find y replace x with -1 in the second equation.

-1 + y = 6

y = -7