Question

What is an equivalent form of the function f(x) = x^2 -8x+15 that reveals the zeros of the function?

Answer 1

Explanation:

The form of a polynomial that reveals the zeroes is factors form.

`y = a(x - r)(x - q)`

where r and q are the zeroes of the function.

So we need to unFOiL this method

We need two number that multiply to 15, but add to -8

So let find two numbers that

The factors of 15 are 1,3,5,15,-1,-3,-5,-15

Since our middle term is negative and our last term is positive, we have two negative roots.

That would just turn out to be -3, and -5

So we get

`y = (x + 3)(x + 5)`

Which reveals the zeroes as -3 and -5