I'm going to use n instead of t
rⁿ=6.25rⁿ+2
minus rⁿ both sides
0=5.25rⁿ+2
minus 2 both sides
-2=5.25rⁿ
divide both sides by 5.25
-2/5.25=rⁿ
take the nth root of both sides
[tex]\sqrt[n]{\frac{-2}{5.25}}= \sqrt[n]{r^n}[/tex]
[tex]\sqrt[n]{\frac{-2}{5.25}}= r[/tex]