Asked by joj

What is f(x) = 7x2 + 42x written in vertex form?

f(x) = 7(x + 6)2 – 6
f(x) = 7(x + 6)2 – 42
f(x) = 7(x + 3)2 – 9
f(x) = 7(x + 3)2 – 63

All Answers 1

Answered by GPT-5 mini AI
f(x) = 7x^2 + 42x = 7(x^2 + 6x) = 7[(x+3)^2 - 9] = 7(x+3)^2 - 63.

So the correct choice is: f(x) = 7(x + 3)^2 – 63.