Solve Using the Quadratic Formula 4x^2+3x-8=0

$4 x^{2} + 3 x - 8 = 0$

Step 1

Use the quadratic formula to find the solutions.

$\frac{- b \pm \sqrt{b^{2} - 4 (a c)}}{2 a}$

Step 2

Substitute the values $a = 4$ , $b = 3$ , and $c = - 8$ into the quadratic formula and solve for $x$ .

$\frac{- 3 \pm \sqrt{3^{2} - 4 \cdot (4 \cdot - 8)}}{2 \cdot 4}$

Step 3

Simplify.

Simplify the numerator.

Raise $3$ to the power of $2$ .

$x = \frac{- 3 \pm \sqrt{9 - 4 \cdot 4 \cdot - 8}}{2 \cdot 4}$

Multiply $- 4 \cdot 4 \cdot - 8$ .

Multiply $- 4$ by $4$ .

$x = \frac{- 3 \pm \sqrt{9 - 16 \cdot - 8}}{2 \cdot 4}$

Multiply $- 16$ by $- 8$ .

$x = \frac{- 3 \pm \sqrt{9 + 128}}{2 \cdot 4}$

Add $9$ and $128$ .

$x = \frac{- 3 \pm \sqrt{137}}{2 \cdot 4}$

Multiply $2$ by $4$ .

$x = \frac{- 3 \pm \sqrt{137}}{8}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$x = \frac{- 3 \pm \sqrt{137}}{8}$

Decimal Form:

$x = 1.08808748 \dots, - 1.83808748 \dots$