Question

Factor to find the zeros of the function defined by the quadratic expression. −7x2 − 91x − 280

Answer 1

There are no zeroes for an expression, only for equations.
Assuming equation to be
−7x^2 − 91x − 280=0
-7(x^2+13x+40)=0
-7(x+8)(x+5)=0
by the zero product properties, 
x+8=0 => x=-8
or 
x+5=0 => x=-5