Question

Solve x ^ 2 - 3x = - 8 using the quadratic formula.

Answer 1

Answer: $\frac{3 +- \sqrt{23}i}{2}$ If using complex numbers, or undefined if using all real numbers

Step-by-step explanation:

Moving -8 to the left side of the eq by adding both sides by 8=

x^2-3x+8=0

The quad formula:$\frac{-b +- \sqrt{b^2-4ac}}{2a}$

a=1 b=-3 c=8

Inserting a b c values into formula: $\frac{-(-3) +- \sqrt{(-3)^2-4(1)(8)}}{2(1)}$

Simplifying: $\frac{3 +- \sqrt{9-32}}{2}$

$\frac{3 +- \sqrt{-23}}{2}$  Since the square root of a negative number doesn't exist in the set of real numbers, the equation is undefined.

OR

$\frac{3 +- \sqrt{23}i}{2}$ Using complex numbers i, to replace the negative number created by subtracting 9-32.