5x+2y=21-x-y=-9 what is the answer
5x + 2y = 21 ⇒ 5x + 2y = 21 -1x - 1y = -9 ⇒ 5x + 5y = 45 -3y = -24 -3 -3 y = 8 5x + 2(8) = 21 5x + 16 = 21 - 16 - 16 5x = 5 5 5 x = 1 (x, y) = (1, 8)