Question

Find the value of “x” in the equation 2a2 + 2xa + 5x + 10 if (a + x) is one of its factors.

Answer 1

Answer:

Say, f(a) = 2a2 + 2xa + 5x + 10

Since, (a + x) is a factor of 2a2 + 2xa + 5x + 10, f(-x) = 0

So, f(-x) = 2x2 – 2x2 – 5x + 10 = 0

Or, -5x + 10 = 0

Thus, x = 2