(3x^2)-(8x)-(7)=0

Solution for (3x^2)-(8x)-(7)=0 equation:

(3x^2)-(8x)-(7)=0

a = 3; b = -8; c = -7;
Δ = b2-4ac
Δ = -82-4·3·(-7)
Δ = 148
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{148}=\sqrt{4*37}=\sqrt{4}*\sqrt{37}=2\sqrt{37}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-8)-2\sqrt{37}}{2*3}=\frac{8-2\sqrt{37}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8)+2\sqrt{37}}{2*3}=\frac{8+2\sqrt{37}}{6}
$