# Quadratics and other Polynomials (photo attachment)

• May 1st 2013, 11:05 PM
dumbblonde
Quadratics and other Polynomials (photo attachment)
Sorry if i posted this in the wrong section.

In the attachment, i posted a photo of what i need help with.

As you will see (if the photo actually works..) the first part says y=ax².
I had to substitute numbers in for a, which were a=-2, -1, -1/2, 1/2, 2, 3.
Which i did using a computerised calculator (fx9860emulator) and graphed it. The graph attachment is also there...
anyway, my problem is, it says "Complete a similar style of investigation for the quadratic functions below:
- y=x² + c
- y=x² + bx
- y=(x-a)(x-B)
- y=(x-a)²
- y=(x-h)² + k
- y=ax² + bx + c
Hint: keep 2 of the values (a,b or c) constant and look at the effect of changing the other.
So, am i mean't to substitue random numbers into the letters c, bx and such? or do i use the same formula that a used?
• May 2nd 2013, 02:06 AM
chiro
Re: Quadratics and other Polynomials (photo attachment)
Hey dumbblonde.

Basically it means that you make two constant, and change the other while plotting a few values of x.

So as an example, let a = 1 and c = 1. Then choose a value of b (say 1) and plot a few values of x to get the graph. Then pick a new b (say b = 2) and do the same thing.

Then just look at how the graphs change when you change the value of b.
• May 3rd 2013, 04:30 AM
dumbblonde
Re: Quadratics and other Polynomials (photo attachment)
Thanks! That helped me figure out the ax²+bx+c but i don't get how to work out y=(x-h)²+k... what am i mean to put here?
• May 3rd 2013, 04:08 PM
chiro
Re: Quadratics and other Polynomials (photo attachment)
For that problem, you take y = x^2, shift it h units to the right to get y = (x-h)^2 and then move the graph up k units to y = (x-h)^2 + k for some constants h and k that you pick and fix.
• May 3rd 2013, 04:37 PM
dumbblonde
Re: Quadratics and other Polynomials (photo attachment)
Okay, i thought so! Thank you! You've helped alot!!