# How do you solve 8x^2 - 10x - 25 = 0 ?

Apr 29, 2016

$- \frac{5}{4} \mathmr{and} \frac{5}{2}$

#### Explanation:

$y = 8 {x}^{2} - 10 x - 25 = 0$
Use the new Transforming Method (Google, Yahoo Search)
Transformed equation $y ' = {x}^{2} - 10 x - 200 = 0$
The 2 roots of y' have opposite signs because ac < 0.
Factor pairs of (ac = -200) -->...(-5, 40)(-10, 20). This last sum is 10 = -b. Therefor the 2 real roots of y' are: -10 and 20.
Back to original y, the 2 real roots are:
$x = - \frac{10}{8} = - \frac{5}{4}$ and $x = \frac{20}{8} = \frac{5}{2}$