Question

Find the roots of the quadratic equation by using the quadratic formula in the following:

–x² + 7x – 10 = 0

Answer 1

The quadratic formula for finding the roots of quadratic equation

ax² + bx + c = 0, a ≠ 0 is given by,

x = ${\displaystyle \frac{-b\pm \sqrt{b^2-4ac}}{2a}}$

∴ x = ${\displaystyle \frac{-7\pm \sqrt{{(-7)}^2-4(-1)(-10)}}{2(-1)}}$

= ${\displaystyle \frac{-7\pm \sqrt{9}}{-2}}$

= ${\displaystyle \frac{7\pm 3}{2}}$

= 5, 2