25r^2=49

Solution for 25r^2=49 equation:

25r^2=49

We move all terms to the left:

25r^2-(49)=0

a = 25; b = 0; c = -49;
Δ = b2-4ac
Δ = 02-4·25·(-49)
Δ = 4900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4900}=70$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-70}{2*25}=\frac{-70}{50}
=-1+2/5
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+70}{2*25}=\frac{70}{50}
=1+2/5
$