Question

Find the value of k so that x = -1 and y =-1 is a solution of the linear equation 9kx + 12ky = 63

Answer 1

k = - 3

Explanation:

Given

9kx + 12ky = 63

Since x = - 1 and y = - 1 are solutions of the equation

Substitute x = - 1 and y = - 1 into the equation and solve for k

9k(- 1) + 12k(- 1) = 63, that is

- 9k - 12k = 63

- 21k = 63 ( divide both sides by - 21 )

k = - 3