Question 25346
x2-81 
I think this one also is suppose to equal 0?
{{{x^2}}}-81=0
(x-9)(x+9)=0
x-9=0
x=9
x+9=0
x=-9
x2-25=0 
(x-5)(x+5)=0
x-5=0
x=5
x+5=0
x=-5
x2-2x-15=0
(x-5)(x+3)=0
x-5=0
x=5
x+3=0
x=-3
Hope you understand
=)
P.S. We are not all sirs, do I still earn a seat at your round table?