Question

Find the value of x2+4x+5=0​

Answer 1

6x= -5

x= -5/6 is the answer

Answer 2

Solution:-

=> x² + 4x + 5 = 0

we solve it by complete square method.

=> x² + 4x = - 5

Add both side 4

=> x² + 4x + 4 = - 5 + 4

=> x² + 4x + 4 = - 1

=> x² + 2x + 2x + 4 = - 1

=> x( x + 2 ) + 2( x + 2 ) = - 1

=> ( x + 2 ) ( x + 2 ) = - 1

=> ( x + 2 )² = - 1

=> x + 2 = √- 1

( in Math, i is called the imaginary

unit. It satisfies i² = -1. Both i and

-i are the square roots of -1 .

since a square root has two values, one positive and the other negative).

=> x = √1 - 2

so now

=> x = - 2 + √1 • i

=> x = - 2 - √1 • i

Note :- ( i used because of imaginary number. )

i hope it helps you.