(4p-5)(p+7)=0

Solution for (4p-5)(p+7)=0 equation:

(4p-5)(p+7)=0

We multiply parentheses ..

(+4p^2+28p-5p-35)=0

We get rid of parentheses

4p^2+28p-5p-35=0

We add all the numbers together, and all the variables

4p^2+23p-35=0

a = 4; b = 23; c = -35;
Δ = b2-4ac
Δ = 232-4·4·(-35)
Δ = 1089
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1089}=33$
$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(23)-33}{2*4}=\frac{-56}{8}
=-7
$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(23)+33}{2*4}=\frac{10}{8}
=1+1/4
$