10a2-7a-12=0

Solution for 10a2-7a-12=0 equation:

10a^2-7a-12=0

a = 10; b = -7; c = -12;
Δ = b2-4ac
Δ = -72-4·10·(-12)
Δ = 529
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{529}=23$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-23}{2*10}=\frac{-16}{20}
=-4/5
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+23}{2*10}=\frac{30}{20}
=1+1/2
$