Since this equation is equal to zero, one of the factors has to equal zero. For example 0 x anything will equal zero. So set each individual factor to zero
X=0
(X-3)=0
(X+6)=0
(X-7)=0
So the first one is just zero X=0
Add 3 to the other side X=3
Subtract 6 X=-6
Add 7 X=7
So your zeros would be X=0,3,-6,7
