Solve the equation by the quadratic formula.
-$$x ^ { 2 } + 4 = 0$$
A)2
B) $$2 \mathrm { i }$$
C) $$\pm 2 \mathrm { i }$$
D) $$\pm 2$$

Question

Quizplus · Accepted Answer

The quadratic formula is $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$. For the equation $x^2 + 4 = 0$, $a = 1$, $b = 0$, and $c = 4$. Plugging these into the formula gives $$x = \frac{-0 \pm \sqrt{0 - 4(1)(4)}}{2(1)} = \frac{\pm \sqrt{-16}}{2} = \pm 2i$$.

Solve the Equation by the Quadratic Formula x2+4=0x ^ { 2 } + 4 = 0x2+4=0

Solve the Equation by the Quadratic Formula $x ^ { 2 } + 4 = 0$