How do you use the quadratic formula to solve x^2+5=4xx2+5=4x?

1 Answer
May 3, 2015

The quadratic formula:
(-b+-sqrt(b^2-4ac))/(2a)b±b24ac2a
can be used to find root solutions to quadratics in the form
ax^2+bx+c = 0ax2+bx+c=0

So first we need to convert the given equation into this form:
x^2+5 = 4xx2+5=4x

rarr x^2-4x+5 = 0x24x+5=0

Solutions are
x= (-(-4) +- sqrt((-4)^2 -4(1)(5)))/(2(1))x=(4)±(4)24(1)(5)2(1)

x= 2+-sqrt((-4))/2x=2±(4)2

Since the discriminant is negative
there are no Real value solutions to this equation
but within Complex numbers, the solution is
x=2+-ix=2±i