Y=-4.9x^2+14.7x+58.8

Solution for Y=-4.9x^2+14.7x+58.8 equation:

=-4.9Y^2+14.7Y+58.8

We move all terms to the left:

-(-4.9Y^2+14.7Y+58.8)=0

We get rid of parentheses

4.9Y^2-14.7Y-58.8=0

a = 4.9; b = -14.7; c = -58.8;
Δ = b2-4ac
Δ = -14.72-4·4.9·(-58.8)
Δ = 1368.57
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-14.7)-\sqrt{1368.57}}{2*4.9}=\frac{14.7-\sqrt{1368.57}}{9.8}
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-14.7)+\sqrt{1368.57}}{2*4.9}=\frac{14.7+\sqrt{1368.57}}{9.8}
$