Question

What is the vertex for the graph of y = -3x2 + 18x - 13?
Answer

(-3, -40)

(-3, -94)

(3, 23)

(3, 14)

Answer 1

The last one

Answer 2

y'=-6x+18=0 so x=3 plug it back into your equation and you'll get y=14 so your vetex is (3,14)

Answer 3

I loved that nenad - I will teach my son :)

Answer 4

haha :D how old is he?

Answer 5

17 - will be taking calc next year. He is in algebra 2 now , your method teaches to stones at once. :)

Answer 6

awesome! :D say hello to him :D

Answer 7

@Maria, practice makes perfect!

Vertex ( h, k)
h = - (b/2a) = - ( 18/-6) = 3

f (3 ) = -3 (3)^2 + 18 (3) - 13 = ...