Question

what number must you add to the polynomial below to complete the square
x^2-4x

Answer 1

Take half of the x term to get (-4/2) = -2


Then square that result to get (-2)^2 = (-2)*(-2) = 4


So you must add 4 to complete the square

Answer 2

thank-you!!!

Answer 3

This will make x^2-4x into x^2-4x+4 which factors to (x-2)^2 and this is a perfect square.

Answer 4

You're welcome