Solve the equation using the quadratic formula.
-$$7 x ^ { 2 } + 10 x + 2 = 0$$
A) $x = \frac { - 5 + \sqrt { 11 } } { 14 }$ or $x = \frac { - 5 - \sqrt { 11 } } { 14 }$
B) $x = \frac { - 10 + \sqrt { 11 } } { 7 }$ or $x = \frac { - 10 - \sqrt { 11 } } { 7 }$
C) $x = \frac { - 5 + \sqrt { 39 } } { 7 }$ or $x = \frac { - 5 - \sqrt { 39 } } { 7 }$
D) $x = \frac { - 5 + \sqrt { 11 } } { 7 }$ or $x = \frac { - 5 - \sqrt { 11 } } { 7 }$

Question

Quizplus · Accepted Answer

The quadratic formula is $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$. For the equation $7x^2 + 10x + 2 = 0$, $a = 7$, $b = 10$, and $c = 2$. Substituting these values gives $x = \frac{-10 \pm \sqrt{10^2 - 4 \cdot 7 \cdot 2}}{2 \cdot 7} = \frac{-10 \pm \sqrt{100 - 56}}{14} = \frac{-10 \pm \sqrt{44}}{14} = \frac{-10 \pm 2\sqrt{11}}{14} = \frac{-5 \pm \sqrt{11}}{7}$.

Solve the Equation Using the Quadratic Formula 7x2+10x+2=07 x ^ { 2 } + 10 x + 2 = 07x2+10x+2=0

Solve the Equation Using the Quadratic Formula $7 x ^ { 2 } + 10 x + 2 = 0$