Question

if x-2 is a factor of x^2-3ax-2a then a=​

Answer 1

Answer:

$let \\ \: f(x) = {x}^{2} +3ax - 2a \\ g(x) = x - 2 \\ x - 2 = 0 \\ x = 2 \\ f(2) = {2}^{2} + 3a(2) - 2a \\ 4 + 6a - 2a = 0 \\ 4 + 4a = 0 \\ 4(1 + a) = 0 \\ a + 1 = 0 \\ a = - 1$