What is the solution set of the inequality x^2-x>20?

a)x>5
b)-4<x<5
c)x>5 or x<-4
d)x>0

3 answers

Factor x^2 -x -20 = 0

There are zeroes at x= 5 and x = -4.
In between -4 and 5, x^2 -x is less than 20. Therefore the answer is not b)

Take it from there
please help more
The Answer in c - x>5 or x<-4
as when x is less than -4 the inequality holds true as well as when x is greater than 5 it is still true.