Question

Which quadratic equation is equivalent to (x – 4)2 – (x – 4) – 6 = 0?
(u – 4)2 – (u – 4) – 6 = 0 where u = (x – 4)
u2 – (u – 4) – 6 = 0 where u = (x – 4)
u2 – 16 – u – 6 = 0 where u = (x – 4)
u2 – u – 6 = 0 where u = (x – 4)

Answer 1

The correct choice is: u^2 − u − 6 = 0 where u = (x − 4).

Reason: letting u = x − 4 gives (x − 4)^2 − (x − 4) − 6 = u^2 − u − 6 = 0.