Question

What is the vertex for the function? y = x2 - 4x - 3
(-1, 2)
(0, -3)
(1, -6)
(2, -7
@jim_thompson

Answer 1

you did this one last night?

Answer 2

I know how to get one of the vertex which is x=4 well how do I find y

Answer 3

it's not x = 4

Answer 4

x = -b/(2a)

x = -(-4)/(2*1)

x = 4/2

x = 2

Answer 5

the x coordinate of the vertex is x = 2

plug it into the function to find y

Answer 6

Follow the steps Jim did and find the function of y.

Answer 7

how did you get 2?

Answer 8

in this case, b = -4 and a = 1

you then plug those into x =-b/(2a) to get x = 2

Answer 9

remember that

y = x^2 - 4x - 3

is the same as

y = 1x^2 - 4x - 3

Answer 10

o okay thank you!

Answer 11

sure thing