Question

1. Which quadratic has x-intercepts at (-3, 0) and (5, 0)?

a) f (x) = (x - 3)(x + 5)
b) f (x) = x^2 - 3x + 5
c) f (x) = (x + 3)(x - 5)
d) f (x) = x^2 + 3x - 5

Answer 1

c

Explanation:

Since the x-intercepts of the quadratic function are (-3,0) and (5,0), so its roots are
`x=-3` and
`x=5`

So, the quadratic function contains the linear factors
`(x+3)` and
`(x-5)`. Then, the quadratic function in the factored form would be, where a is a real number:

`f(x)=a(x+3)(x-5)`

For simplicity, assume that
`a=1` and the quadratic function becomes:

`f(x)=(x+3)(x-5)`