-4.9x^2+14.7x=9.8

Solution for -4.9x^2+14.7x=9.8 equation:

-4.9x^2+14.7x=9.8

We move all terms to the left:

-4.9x^2+14.7x-(9.8)=0

We add all the numbers together, and all the variables

-4.9x^2+14.7x-9.8=0

a = -4.9; b = 14.7; c = -9.8;
Δ = b2-4ac
Δ = 14.72-4·(-4.9)·(-9.8)
Δ = 24.01
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{-(14.7)-\sqrt{24.01}}{2*-4.9}=\frac{-14.7-\sqrt{24.01}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14.7)+\sqrt{24.01}}{2*-4.9}=\frac{-14.7+\sqrt{24.01}}{-9.8}
$