Question

8x2 +43x +30=0solve for x

Answer 1

Use the quadratic formula to find the values of x:

`x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a}`

Where a, b and c are the coefficients of the quadratic equation.

`\begin{gathered} x=\frac{-43\pm\sqrt[]{43^2-4\cdot8\cdot30}}{2\cdot8} \\ x=\frac{-43\pm\sqrt[]{1849-960}}{16} \\ x=\frac{-43\pm\sqrt[]{889}}{16} \end{gathered}`

The equation has two solutions for x.

`\begin{gathered} x1=\frac{-43+\sqrt[]{889}}{16} \\ x2=\frac{-43-\sqrt[]{889}}{16} \end{gathered}`

As decimal numbers:

`\begin{gathered} x1=-0.8239 \\ x2=-4.5510 \end{gathered}`