Select all the correct answers.

What are the [tex]$x$[/tex]-intercepts of the graph of the quadratic function [tex]$f(x)=3(x-1)(x+3)$[/tex]?

A. [tex]$(3,0)$[/tex]
B. [tex]$(-3,0)$[/tex]
C. [tex]$(-1,0)$[/tex]
D. [tex]$(1,0)$[/tex]
E. [tex]$(3,1)$[/tex]
F. [tex]$(-3,-1)$[/tex]



Answer :

To determine the [tex]\( x \)[/tex]-intercepts of the quadratic function [tex]\( f(x) = 3(x-1)(x+3) \)[/tex], we need to find the points where the function [tex]\( f(x) \)[/tex] equals zero. These points occur when either of the factors [tex]\( (x-1) \)[/tex] or [tex]\( (x+3) \)[/tex] equal zero.

Let's solve for the [tex]\( x \)[/tex]-intercepts step-by-step:

1. Identify the factors: The quadratic function is given in factored form as [tex]\( f(x) = 3(x-1)(x+3) \)[/tex].

2. Set the function equal to zero: To find the [tex]\( x \)[/tex]-intercepts, set [tex]\( f(x) = 0 \)[/tex]:
[tex]\[ 3(x-1)(x+3) = 0 \][/tex]

3. Solve for each factor equal to zero:
- First factor: [tex]\( x-1 = 0 \)[/tex]
[tex]\[ x-1 = 0 \implies x = 1 \][/tex]
- Second factor: [tex]\( x+3 = 0 \)[/tex]
[tex]\[ x+3 = 0 \implies x = -3 \][/tex]

4. Determine the [tex]\( x \)[/tex]-intercepts: The solutions [tex]\( x = 1 \)[/tex] and [tex]\( x = -3 \)[/tex] are the values where the function crosses the [tex]\( x \)[/tex]-axis. Therefore, the corresponding [tex]\( x \)[/tex]-intercepts are [tex]\( (1, 0) \)[/tex] and [tex]\( (-3, 0) \)[/tex].

So, the correct [tex]\( x \)[/tex]-intercepts for the graph of the quadratic function [tex]\( f(x) = 3(x-1)(x+3) \)[/tex] are [tex]\( (1, 0) \)[/tex] and [tex]\( (-3, 0) \)[/tex].

Looking at the answer choices:

- [tex]\((3, 0)\)[/tex]
- [tex]\((-3, 0)\)[/tex] ✅
- [tex]\((-1, 0)\)[/tex]
- [tex]\((1, 0)\)[/tex] ✅
- [tex]\((3, 1)\)[/tex]
- [tex]\((-3, -1)\)[/tex]

The correct [tex]\( x \)[/tex]-intercepts are [tex]\((-3, 0)\)[/tex] and [tex]\((1, 0)\)[/tex]. Therefore, the correct answers are:

- [tex]\((-3, 0)\)[/tex]
- [tex]\((1, 0)\)[/tex]