What is the vertex of g(x) = –3x2 + 18x + 2?

Question

asked Jun 26, 2021 117k views

2 Answers

Darko Kenda · Answer 1 · 2021-07-02T06:53:59+0000

Answer:

(3,29)

Explanation:

There is a formula that can be used to find the x-value of the vertex of the parabola. This formula is
x=(-b)/(2a)

We have the function
g(x)=-3x^2+18x+2

From this function, we can find that

$a=-3\\b=18\\c=2$

We can plug in our know values into the formula to get

$x=(-18)/(2(-3)\\) \\x=(-18)/(-6) \\\\x=3$

Then we can plug in our x-value to find the y-value of the vertex

$g(3)=-3(3)^2+18(3)+2\\\\g(3)=-3(9)+54+2\\\\g(3)=-27+54+2\\\\g(3)=29$

This means that the vertex would be
(3,29)