3a2=-25a-42

Solution for 3a2=-25a-42 equation:

3a^2=-25a-42

We move all terms to the left:

3a^2-(-25a-42)=0

We get rid of parentheses

3a^2+25a+42=0

a = 3; b = 25; c = +42;
Δ = b2-4ac
Δ = 252-4·3·42
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(25)-11}{2*3}=\frac{-36}{6}
=-6
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(25)+11}{2*3}=\frac{-14}{6}
=-2+1/3
$