Question

What are the x-intercepts of the graph of the function f(x) = x2 + 4x – 12?

(–6, 0), (2,0)
(–2, –16), (0, –12)
(–6, 0), (–2, –16), (2, 0)
(0, –12), (–6, 0), (2, 0)​

Answer 1

(-6,0),(2,0)

Explanation:

x-intercept

at x-intercept y=0

f(x)=x^2+4x-12

x^2+4x-12=0

by using factorisation method

product=-12

sum=4

factors=6,-2

(x^2 -2x)+(6x-12)=0

x(x-2)+6(x-2)=0

(x+6)(x-2)=0

x+6=0, x-2=0

x= -6,x=2

Answer 2

The x intercepts would be (-6; 0) and (2; 0).

Explanation:

Take a look at the picture.

Calculate it replacing f(x) with 0. The result will be: x1 = -6, x2 = 2 (consequently, both y's equal 0).