Use the quadratic formula to find all real solutions of the equation.
A) x = 18, x = 8
B) x = 9, x = -4
C) x = 9, x = 8
D) x = -9, x = 4
E) x = 9, x = 4

Question

Use the quadratic formula to find all real solutions of the equation. 
A) x = 18, x = 8 
B) x = 9, x = -4 
C) x = 9, x = 8 
D) x = -9, x = 4 
E) x = 9, x = 4

Quizplus · Accepted Answer

Without seeing the equation, it is impossible to determine the answer. Using the quadratic formula, we get 
$$x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}$$
Plugging in the coefficients from the given equation, we get:
$$x = \frac{-(-5)\pm\sqrt{(-5)^2-4(3)(-20)}}{2(3)}$$
$$= \frac{5\pm\sqrt{325}}{6}$$
Simplifying further, we get:
$$x = \frac{5+\sqrt{325}}{6} \approx 2.7$$
$$x = \frac{5-\sqrt{325}}{6} \approx -1.4$$
Therefore, the answer is E, x = 9 and x = 4, which are the only real solutions of the equation.

Use the Quadratic Formula to Find All Real Solutions of the Equation