Quadratic Function Q&A: Working w/ Numbers Below 10

[hell18]

2 questions

1.can a quadratic function be just set to 1 number e.g. 5 or can it be a bigger number. at the moment I am working on numbers below 10 to get used to the formulas.

2. is this correct how i am doing it?

formula

N --> N²--> 3N² + 4

e.g.

N =5

5 x 5 = 25 = N²

5 x 25 = 75 = 3N²

N = 79 answer

is that correct?

 

[HallsofIvy]

Your questions are awkwardly written but I think what you want is:

given y= ax²+ bx+ c, you can choose x to be any number you want, then calculate y.

In particular, if y= 3N²+ 4, you would, just as you say, first, find N², then multiply by 3, then add 4.

 

[hell18]

thats it, yea I am still practicing the equations. i thought Y² were that if you had Y = 5 then Y². Then to find Y² we multiply the 5 by in this case Y² to get 25 as Y² would be 25 then mutliply 3N² by the 25 to get 75 + 4 to get 79

is that ok?

 

[HallsofIvy]

I'm assuming that English is not your native language so I won't be quite as harsh as I could be!

that's it, yea I am still practicing the equations. i thought Y² were that if you had Y = 5 then Y². Then to find Y² we multiply the 5 by in this case Y² to get 25 as Y² would be 25 then mutliply 3N² by the 25 to get 75 + 4 to get 79

Much of this makes no since at all: "i thought Y² were that if you had Y = 5 then Y²." Then what?? I assume you meant to write "then Y²= 5²".

But you also write "Then to find Y² we multiply the 5 by in this case Y²". No, you multiply 5 by itself- that's what "²" means.

"then mutliply 3N² by the 25". No, "N²" is 25. You only multiply the 3 by 25. By the way, it's a really, really bad idea to suddenly switch from "Y" to "N".

To calculate 3N²+ 4, for N= 5, you replace the N by 5:
3(5)²+ 4= 3(25)+ 4= 75+ 4= 79.