WAEC 2022 · Paper 1 · Q16

Quadratics & their graphs

What value of $p$ will make $(x^2 - 4x + p)$ a perfect square?

Worked solution (try it first)

To complete the square, add the square of half the coefficient of $x$ .
Half of $-4$ is $-2$ , and $(-2)^2 = 4$ .
So $x^2 - 4x + 4 = (x - 2)^2$ and $p = 4$ , option C.

Report a problem with this question