4.9x^2+3x-7.5=0

Solution for 4.9x^2+3x-7.5=0 equation:

4.9x^2+3x-7.5=0

a = 4.9; b = 3; c = -7.5;
Δ = b2-4ac
Δ = 32-4·4.9·(-7.5)
Δ = 156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{156}=\sqrt{4*39}=\sqrt{4}*\sqrt{39}=2\sqrt{39}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-2\sqrt{39}}{2*4.9}=\frac{-3-2\sqrt{39}}{9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+2\sqrt{39}}{2*4.9}=\frac{-3+2\sqrt{39}}{9.8}
$