Question

Which ordered pair in the form (x, y) is a solution of this equation?

(x + 6)y = 9


4, 1)

(2, 1)

(3, 1)

(12, 2)

Answer 1

(3, 1)

substitute each ordered pair into the left side of the equation and if equal to the right side then it is a solution

(4, 1 )

(4 + 6) × 1 = 10 × 1 = 10 ≠ 9 ← not a solution

(2, 1 )

(2 + 6 ) × 1 = 8 × 1 = 8 ≠ 9 ← not a solution

(3, 1 )

(3 + 6 ) × 1 = 9 × 1 = 9 ← hence a solution

(12, 2 )

(12 + 6 ) × 2 = 18 × 2 = 36 ≠ 9 ← not a solution