Question

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

Answer 1

D: u2 – u – 6 = 0 where u = (x – 4)

Explanation:

got it right on the test

Answer 2

I hope choices must be given in the problem.

I am showing the method to find the equivalent equation of the above equation. You can match with your given choices.

First step is to expand the first term. So,

(x-4)² = (x - 4)(x - 4) Since a²= a*a

= x² - 4x - 4x + 4 * 4 By multiplying.

= x² -8x + 16 Combine the like terms.

So, (x - 4)² - (x -4) - 6

= x² - 8x + 16 - x + 4 - 6

= x² - 9x + 14 Combine the like terms.

So, equivalent equation of the above equation is x² - 9x + 14 = 0.