0=-4.9x^2+14x+30

Solution for 0=-4.9x^2+14x+30 equation:

0=-4.9x^2+14x+30

We move all terms to the left:

0-(-4.9x^2+14x+30)=0

We add all the numbers together, and all the variables

-(-4.9x^2+14x+30)=0

We get rid of parentheses

4.9x^2-14x-30=0

a = 4.9; b = -14; c = -30;
Δ = b2-4ac
Δ = -142-4·4.9·(-30)
Δ = 784
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{784}=28$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-14)-28}{2*4.9}=\frac{-14}{9.8}
=-1+3.5/8.1666666666667
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-14)+28}{2*4.9}=\frac{42}{9.8}