Question

How do i solve x squared = 4x -5

Answer 1

Answer:

x = 2 ±i

Step-by-step explanation:

x^2 = 4x-5

Subtract 4x from each side

x^2 - 4x = 4x-5 -4x

x^2 - 4x= -5

Complete the square

Take the coefficient of the x term, divide by 2 and square it

-4/2 =2   2^2 =4

Add 4 to each side

x^2 -4x+4 = -5 +4

The left side is (x-coefficient of the x term/2)^2

(x-2)^2 = -1

Take the square root of each side

sqrt((x-2)^2) = sqrt(-1)

x-2 = ±i

Add 2 to each side

x-2+2 = 2 ±i

x = 2 ±i