Question

In the function f(x) = 4(x2 − 6x + ____) + 20, what number belongs in the blank to complete the square?

Answer 1

Hello :
f(x) = 4(x2 − 6x + 3² - 3²____) + 20 = 4((x2 − 6x + 3²) - 3²____) + 20
      = 4(x-3)² -36+20
f(x) = 4(x-3)² -16 (vertex form)