which are the solutions of the quadratic equation? x2 = –5x – 3
\(x^2=-5x-3\\x^2+5x+3=0\\\\a=1;\ b=5;\ c=3\\\Delta=b^2-4ac\\\\\Delta=5^2-4\cdot1\cdot3=25-12=13 \ \textgreater \ 0\\\\therefore\\x_1=\dfrac{-b-\sqrt\Delta}{2a}\ and\ x_2=\dfrac{-b+\sqrt\Delta}{2a}\\\\x_1=\dfrac{-5-\sqrt{13}}{2\cdot1}=\boxed{\dfrac{-5-\sqrt{13}}{2}}\\\\x_2=\dfrac{-5+\sqrt{13}}{2\cdot1}=\boxed{\dfrac{-5+\sqrt{13}}{2}}\)
Answer
Find out the solutions of the quadratic equation.
x² = –5x – 3
To prove
As the quadratic equation be.
x² + 5x + 3 = 0
Discriminant Formula
\(x = \frac{-b\pm\sqrt{b^{2} -4ac} }{2a}\)
As a = 1 , b = 5 , c = 3
Put in the formula
\(x = \frac{-5\pm\sqrt{5^{2} -4\times 1\times 3} }{2\times 1}\)
\(x = \frac{-5\pm\sqrt{25 -12} }{2\times 1}\)
\(x = \frac{-5\pm\sqrt{13} }{2\times 1}\)
Thus the solutions of x² = –5x – 3 are
\(x = \frac{-5\ +\sqrt{13} }{2}\)
and
\(x = \frac{-5\ -\sqrt{13} }{2}\)