7p(3p+4)=0

Solution for 7p(3p+4)=0 equation:

7p(3p+4)=0

We multiply parentheses

21p^2+28p=0

a = 21; b = 28; c = 0;
Δ = b2-4ac
Δ = 282-4·21·0
Δ = 784
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{784}=28$
$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(28)-28}{2*21}=\frac{-56}{42}
=-1+1/3
$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(28)+28}{2*21}=\frac{0}{42}
=0
$