X^2+0.7x-0.3=0

Solution for X^2+0.7x-0.3=0 equation:

X^2+0.7X-0.3=0

a = 1; b = 0.7; c = -0.3;
Δ = b2-4ac
Δ = 0.72-4·1·(-0.3)
Δ = 1.69
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{-(0.7)-\sqrt{1.69}}{2*1}=\frac{-0.7-\sqrt{1.69}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.7)+\sqrt{1.69}}{2*1}=\frac{-0.7+\sqrt{1.69}}{2}
$