Question #b48d8

1 Answer
Sep 24, 2015

Answer:

#x=2+isqrt(3),x=2-isqrt(3)#

Explanation:

This quadratic expression should be solved by completing the square.

#f(x)=x^2-4x+7=0#

Minus seven from both sides,

#x^2-4x=-7#

Add four to both sides,

#x^2-4x+4=-3#

Write the left hand side as a square,

#(x-2)^2=-3#

Take the square root of both sides,

#x-2=+-isqrt(3)#

Add two to both sides

#x=2+-isqrt(3)#

or

#x=2+isqrt(3),x=2-isqrt(3)#