49x^2-70x-28=0

Solution for 49x^2-70x-28=0 equation:

49x^2-70x-28=0

a = 49; b = -70; c = -28;
Δ = b2-4ac
Δ = -702-4·49·(-28)
Δ = 10388
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{10388}=\sqrt{196*53}=\sqrt{196}*\sqrt{53}=14\sqrt{53}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-70)-14\sqrt{53}}{2*49}=\frac{70-14\sqrt{53}}{98}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-70)+14\sqrt{53}}{2*49}=\frac{70+14\sqrt{53}}{98}
$