3(z+14)(z+14)-750=0

Solution for 3(z+14)(z+14)-750=0 equation:

3(z+14)(z+14)-750=0

We multiply parentheses ..

3(+z^2+14z+14z+196)-750=0

We multiply parentheses

3z^2+42z+42z+588-750=0

We add all the numbers together, and all the variables

3z^2+84z-162=0

a = 3; b = 84; c = -162;
Δ = b2-4ac
Δ = 842-4·3·(-162)
Δ = 9000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{9000}=\sqrt{900*10}=\sqrt{900}*\sqrt{10}=30\sqrt{10}$
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(84)-30\sqrt{10}}{2*3}=\frac{-84-30\sqrt{10}}{6}
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(84)+30\sqrt{10}}{2*3}=\frac{-84+30\sqrt{10}}{6}
$