13r2-5=203

Solution for 13r2-5=203 equation:

13r^2-5=203

We move all terms to the left:

13r^2-5-(203)=0

We add all the numbers together, and all the variables

13r^2-208=0

a = 13; b = 0; c = -208;
Δ = b2-4ac
Δ = 02-4·13·(-208)
Δ = 10816
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{10816}=104$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-104}{2*13}=\frac{-104}{26}
=-4
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+104}{2*13}=\frac{104}{26}
=4
$