Question

I don't understand how to work this, Please explain and help.

What is the axis of symmetry for the function? y = x2 + 3x - 4

Answer 1

@Mertsj

Answer 2

The axis of symmetry is given by the equation

\[\frac{ -b }{ 2a }\]

Answer 3

graph it first and look for the lowest point. That vertical line through is the axis

Answer 4

\[x^2 = a, 3x = b, -4 = c\]

Answer 5

ok, these are the options I was given...

y = -2
y = -1.5
x = -2
x = -1.5

Answer 6

Okay, so plug it in and do it yourself. \[\frac{ -3 }{ 2(x^2) }\]

Answer 7

it would be
\[\frac{ -3 }{2*1 }\]

Answer 8

\[x^2 = 1\]

It is always assumed that x = 1.

Answer 9

ok...?

Answer 10

Now do the division.

Answer 11

not very good at that.... good at polynomials though.

Answer 12

Do you know that the axis of symmetry is a vertical line that goes through the vertex?

Answer 13

no...

Answer 14

Well you do now. Consider this:

Answer 15

ok