-1.4x^2+1x+30=0

Solution for -1.4x^2+1x+30=0 equation:

-1.4x^2+1x+30=0

We add all the numbers together, and all the variables

-1.4x^2+x+30=0

a = -1.4; b = 1; c = +30;
Δ = b2-4ac
Δ = 12-4·(-1.4)·30
Δ = 169
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{169}=13$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-13}{2*-1.4}=\frac{-14}{-2.8}
=+5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+13}{2*-1.4}=\frac{12}{-2.8}
=-4+0.8/2.8
$