Please help me, I need an answer as soon as possible.
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Answer:
[tex]\huge\boxed{\sf x = \pm \sqrt{7} }[/tex]
Step-by-step explanation:
Given function:
[tex]f(x)=x^2-7[/tex]
We can also write it as:
[tex]y =x^2-7[/tex]
x-intercept is the point where y = 0
Put y = 0 in the above equation
[tex]0=x^2-7\\\\Add \ 7 \ to \ both\ sides\\\\7 = x^2\\\\Take \ sqrt \ on \ both \ sides\\\\\pm \sqrt{7} =x\\\\x = \pm \sqrt{7} \\\\\rule[225]{225}{2}[/tex]