Respuesta :
minus 25 oth sides
x^2+4x-21
facotr
what 2 numbes multiply to -21 and add to 4?
-3 and 7
(x-3)(x+7)=0
set to zero
x-3=0
x=3
x+7=0
x=-7
x=3 or -7
A is answer
x^2+4x-21
facotr
what 2 numbes multiply to -21 and add to 4?
-3 and 7
(x-3)(x+7)=0
set to zero
x-3=0
x=3
x+7=0
x=-7
x=3 or -7
A is answer