Question

x^2-5kx+25 is the square of binomial. What is a possible value of k ?
Please include steps, thanks!

Answer 1

Its\[(x-5)^2 = x^2+25-2(x)(5) = x^2+25-10x so k =2

Answer 2

how did you get that?

Answer 3

\[(a-b)^2 = a^2+b^2-2ab . This is a formula.

Answer 4

what formula?

Answer 5

(a-b)^2 = a^2+b^2-2ab

Answer 6

\[k=\pm 2\]