(x+5)(x-2)
When you are factoring you find the numbers that give you your middle and last term. In this case it would be a negative 2 and a positive 5. Once you do that, have it as (x+5) times (x-2). So it would look like this (x+5)(x-2). Now when you multiply that out to check it would become x^2+3x-10.