Find the x-intercepts of f(x)=4x^2-20.

Question

Give an exact answer using radicals as needed. Rationalize all denominators. Express complex numbers in terms of i.

Answer 1

The x intercept is where f(x) = 0
That would be where 4x^2 = 20, or in other words, where
x^2 = 5
Take the square root of both sides, remembering to use +/-. There should be no denominator to rationalize, so forget about that