Question

x²+4x=7x
x²+6x+8=0
m²+10m+21=0

Answer 1

x^2=3x
x^3-3x=0
x(x-3)=0
x igual a 0
x-3=0
x=3 solucion x= 0 ; 3


2) x^2+6x+8=0
(x+2) (x+4) = 0
x= -2
x= -4 solucion : x= -2 ; -4

3) m^2+10m+21=0
(m+3) (m+7) = 0
m= -3
m= -7 solucion: m= -3 ; -7