-4.9x^2+27x+2.4=30

Solution for -4.9x^2+27x+2.4=30 equation:

-4.9x^2+27x+2.4=30

We move all terms to the left:

-4.9x^2+27x+2.4-(30)=0

We add all the numbers together, and all the variables

-4.9x^2+27x-27.6=0

a = -4.9; b = 27; c = -27.6;
Δ = b2-4ac
Δ = 272-4·(-4.9)·(-27.6)
Δ = 188.04
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{-(27)-\sqrt{188.04}}{2*-4.9}=\frac{-27-\sqrt{188.04}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(27)+\sqrt{188.04}}{2*-4.9}=\frac{-27+\sqrt{188.04}}{-9.8}
$