Respuesta :

answer is x = -7 and x = -3

 x2 + 10x = -21
 x2 + 10x + 21 = 0
(x +3) (x +7) = 0

(x +3) = 0
and
(x + 7) = 0
so x = - 3 and x = -7

Answer:

the 2nd one

Step-by-step explanation: