Question

Find the roots of the quadratic equation x2+5x+6=0​

Answer 1

please please mark my answer as a brainalist please

The roots of a quadratic equation ax^2 + bx + c = 0 are given by 

For the given equation, a = 1, b = 2 and c = 5.

The roots of the equation are:




The roots of the equation are 

MARIA-VIVANCO | STUDENT

1. subtract -5 to both sides:

x^2 +2x=-5

then you find half of what 2 is and add it's square to both sides 

(x+1)^2=-4

Then you square root each side to get rid of the exponent. Since -4 is negative we use i. 

So that becomes x+1=2i

x1: -1+2i

x2: -1-2i

NEELA | STUDENT

To solve the equation x^2+2x+5 = 0. by completing the square.

x^2+2x +5 = 0.

=> x^2+2x = -5.

The left side x^2+2x+becomes a perfect square x^2+2x+1= x^+1^2, if we add 1. So we add 1 to both sides:

=> x^2+2x+1 = -5+1 = -4.

=> (x+1)^2 = -4.

=(x+1)^2 = (2)^2 *(i)^2 , where i^2 = -1.

Therefore x+1 = {(2)^2*i^2}^(1/2) . Or   x+1 = - {(2)^2*i^2}^(1/2).

=> x+1= 2i or x+1= -2i.

Therefore  x = -1+2i. Or x= -(1+2i).