9x^2-40x-49=0

Solution for 9x^2-40x-49=0 equation:

9x^2-40x-49=0

a = 9; b = -40; c = -49;
Δ = b2-4ac
Δ = -402-4·9·(-49)
Δ = 3364
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3364}=58$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-40)-58}{2*9}=\frac{-18}{18}
=-1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-40)+58}{2*9}=\frac{98}{18}
=5+4/9
$