Question

For the solution (2,2) , find the value of ‘c’ in the equation 2x + cy = 8

Answer 1

We have a solution (2,2) so x = 2 and y = 2. Then:

`2x+cy=8\\\\2\cdot2+c\cdot2=8\\\\4+2c=8\\\\2c=8-4\\\\2c=4\quad|:2\\\\\boxed{c=2}`