Answer:
(1, - 2 )
Explanation:
9x - 3y = 15 → (1)
3x + 3y = - 3 → (2)
add (1) and (2) term by term to eliminate y
(9x + 3x) + (- 3y + 3y) = 15 - 3
12x + 0 = 12
12x = 12 ( divide both sides by 12 )
x = 1
substitute x = 1 into either of the 2 equations and solve for y
substituting into (2)
3(1) + 3y = - 3
3 + 3y = - 3 ( subtract 3 from both sides )
3y = - 6 ( divide both sides by 3 )
y = - 2
solution is (1, - 2 )