if 2x^2-(b-4)x-4(b+2)=0

Question

has equal root then.the value of b?

Answer 1

if two roots are identical
then
(b-4)^2 - 4(2)(-4)(b+2) = 0

b^2 - 8 b + 16 = -32b - 64

b^2 + 24 b + 80 = 0
(b+4)(b+20) = 0