Question

Find the $x$ intercept of the parabola $y=3x^2-2x-8$.

• A. $\frac{1}{3}$ and $-25$
• B. $\frac{4}{3}$ and $-2$
• C. $-\frac{4}{3}$ and $2$
• D. $-\frac{4}{3}$ and $-2$

Answer 1

Answer: (C)

$-\frac{4}{3}$ and $2$

To find the $x$- intercept, we need to equate $y$ to $0$.

Doing that, we get $0=3x^2-2x-8$

$\Rightarrow x=\frac{2\pm \sqrt{4+96}}{6}$

$\Rightarrow x=\frac{2\pm 10}{6}$

$\Rightarrow x=\frac{-4}{3},2$