Question 278739
x^2 + 4x - 21 > 0


factoring ___ (x + 7) (x - 3) > 0


for the product to be >0, either both factors are >0 or both factors are <0


for both >0 ___ x > 3


for both <0 ___ x < 7


so, (x < 7) OR (x > 3)