Question

Create a quadratic function, f(x), in vertex form. The a should be between 4 and –4, the h will be your birth month, and the k will be your birth day. Write your equation below.

Answer 1

My birthday is 11/23/96

Answer 2

so h = 11 and k = 23

Answer 3

pick an 'a' value between 4 and -4

Answer 4

then plug all 3 values into

\[\Large y = a(x-h)^2 + k\]

Answer 5

that equation is the general vertex form equation

Answer 6

how about 2

Answer 7

sure a = 2 works

Answer 8

okay now what do I do?

Answer 9

plug a = 2, h = 11, k = 23 into that equation I wrote above

Answer 10

2(x-11)^2+23

Answer 11

correct

Answer 12

Can you help me with the rest of the questions for this problem?

Answer 13

@jim_thompson5910

Answer 14

how many more are there?

Answer 15

5 more

Answer 16

ok we'll see (depends on how long they are)

Answer 17

Using complete sentences, explain how to convert your birthday function into standard form.

Answer 18

so we have 2(x-11)^2+23 which is currently in vertex form

Answer 19

we need to get it into ax^2 + bx + c form

Answer 20

to do that, you need to FOIL or expand out (x-11)^2 first

Answer 21

what does (x-11)^2 expand out to?

Answer 22

(x-11)(x-11)?

Answer 23

FOIL that out

Answer 24

x^2-11x-x^2-11x

Answer 25

how did you get x^2 twice?

Answer 26

oops

Answer 27

to help you expand out (x-11)(x-11), you can use this table