natti23
contestada

Which of the following would best be solved using completing the square?
5x^2+7x=12
X^2+4x-21=0
x^2=81
2x^3-12x^2+5x-30=0

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

Answer:

I think the answer is the last one 2x^3-12x^2+5x-30=0

Step-by-step explanation: