Respuesta :
Answer Second
Step by step exploration
x^2+4x-21=0
x^2+4x+4-25=0
(x+2)^2-25=0
(x+2)^2=25
X+2=+OR-5
x=-7 or x=3
Step by step exploration
x^2+4x-21=0
x^2+4x+4-25=0
(x+2)^2-25=0
(x+2)^2=25
X+2=+OR-5
x=-7 or x=3
Answer:
I think the answer is the last one 2x^3-12x^2+5x-30=0
Step-by-step explanation: