10a-a^2-16=0

Solution for 10a-a^2-16=0 equation:

10a-a^2-16=0

We add all the numbers together, and all the variables

-1a^2+10a-16=0

a = -1; b = 10; c = -16;
Δ = b2-4ac
Δ = 102-4·(-1)·(-16)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-6}{2*-1}=\frac{-16}{-2}
=+8
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+6}{2*-1}=\frac{-4}{-2}
=+2
$