-4=-4.9x^2+24x

Solution for -4=-4.9x^2+24x equation:

-4=-4.9x^2+24x

We move all terms to the left:

-4-(-4.9x^2+24x)=0

We get rid of parentheses

4.9x^2-24x-4=0

a = 4.9; b = -24; c = -4;
Δ = b2-4ac
Δ = -242-4·4.9·(-4)
Δ = 654.4
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{-(-24)-\sqrt{654.4}}{2*4.9}=\frac{24-\sqrt{654.4}}{9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-24)+\sqrt{654.4}}{2*4.9}=\frac{24+\sqrt{654.4}}{9.8}
$