2.1-p2=-4.7

Solution for 2.1-p2=-4.7 equation:

2.1-p2=-4.7

We move all terms to the left:

2.1-p2-(-4.7)=0

We add all the numbers together, and all the variables

-1p^2+6.8=0

a = -1; b = 0; c = +6.8;
Δ = b2-4ac
Δ = 02-4·(-1)·6.8
Δ = 27.2
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$p_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{27.2}}{2*-1}=\frac{0-\sqrt{27.2}}{-2}
=-\frac{\sqrt{}}{-2}
$
$p_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{27.2}}{2*-1}=\frac{0+\sqrt{27.2}}{-2}
=\frac{\sqrt{}}{-2}
$