Question

The pair of variables x=5, y=7 is the solution to the equation ax–2y=1. Find the coefficient a.

Answer 1

a = 3

Explanation:

Put x = 5 and y = 7 to the equation ax - 2y = 1 and solve for a:

(a)(5) - (2)(7) = 1

5a - 14 = 1 add 14 to both sides

5a - 14 + 14 = 1 + 14

5a = 15 divide both sides by 5

5a : 5 = 15 : 5

a = 3