What's the value of c?

Question

If -7 is one solution of the equation y²+cy-35=0, what's the value of c?

Answer 1

Since -7 is a solution of the equation y² + cy - 35 = 0, (-7)²-7c-35 = 0.

 

 So, 49 - 7c - 35 = 0

 

                  -7c = -14

 

                    c = 2

 

 

Answer 2

-7 is a factor of -35. The other is 5.

c = 5 - 7