-4.9x^2+30x+35=0

Solution for -4.9x^2+30x+35=0 equation:

-4.9x^2+30x+35=0

a = -4.9; b = 30; c = +35;
Δ = b2-4ac
Δ = 302-4·(-4.9)·35
Δ = 1586
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-\sqrt{1586}}{2*-4.9}=\frac{-30-\sqrt{1586}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+\sqrt{1586}}{2*-4.9}=\frac{-30+\sqrt{1586}}{-9.8}
$