Solve the equation by using the quadratic formula.
-$$y ^ { 2 } = 4 y - 9$$
A) $\{ 4 \pm 2 i \sqrt { 5 } \}$
B) $\{ - 2 \pm i \sqrt { 5 } \}$
C) $\{ 2 \pm i \sqrt { 5 } \}$
D) $\{ - 4 \pm 2 i \sqrt { 5 } \}$

Question

Quizplus · Accepted Answer

Rearrange the equation to $y^2 - 4y + 9 = 0$. Using the quadratic formula $y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$, where $a = 1$, $b = -4$, and $c = 9$, we find the roots to be $2 \pm i\sqrt{5}$.

Solve the Equation by Using the Quadratic Formula y2=4y−9y ^ { 2 } = 4 y - 9y2=4y−9

Solve the Equation by Using the Quadratic Formula $y ^ { 2 } = 4 y - 9$