2.7x^2-4x-7.7=0

Solution for 2.7x^2-4x-7.7=0 equation:

2.7x^2-4x-7.7=0

a = 2.7; b = -4; c = -7.7;
Δ = b2-4ac
Δ = -42-4·2.7·(-7.7)
Δ = 99.16
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{-(-4)-\sqrt{99.16}}{2*2.7}=\frac{4-\sqrt{99.16}}{5.4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+\sqrt{99.16}}{2*2.7}=\frac{4+\sqrt{99.16}}{5.4}
$