193k views
3 votes
1. Find the roots of x^2 + 5 = -5x

User Persida
by
4.3k points

1 Answer

1 vote

To find the roots of the equation:


x^2+5=-5x

we can use the general formula:


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

First we need to write the equation in the form:


ax^2+bx+c=0

Then the equation given takes the form:


x^2+5x+5=0

now we identify that a=1, b=5 and c=5. Plugging this values into the general formual we have:


\begin{gathered} x=\frac{-5\pm\sqrt[]{5^2-4(1)(5)}}{2(1)} \\ =\frac{-5\pm\sqrt[]{25-20}}{2} \\ =\frac{-5\pm\sqrt[]{5}}{2} \end{gathered}

Hence the roots are:


\begin{gathered} x=\frac{-5+\sqrt[]{5}}{2} \\ \text{and} \\ x=\frac{-5-\sqrt[]{5}}{2} \end{gathered}

User Cosmin D
by
4.5k points