Express f in standard form.

Question

f(x) = x² + 6x

Answer 1

The function is already in standard form. If you wanted to do vertex form though, you would complete the square as shown below:

f(x) = x²+6x

f(x)+9 = x²+6x+9

f(x)+9 = (x+3)²

f(x) = (x+3)²-9

You can also write it in factored form as f(x) = x(x+6) since x is the GCF of the RHS expression.