How do you solve $5^{- \frac{t}{2}} = 0.20$ $5^(-t/2)=0.20$ ?

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Answer 1 · 2017-01-03T08:45:44

$t = 2$ $t=2$

$5^{- \frac{t}{2}} = 0.2$ $5^(-t/2)=0.2$

see if RHS can be expressed as a power of $5$ $" "5$
change RHS to a fraction

$5^{- \frac{t}{2}} = \frac{1}{5}$ $5^(-t/2)=1/5$

$5^{- \frac{t}{2}} = 5^{- 1}$ $5^(-t/2)=5^(-1)$

$\Rightarrow \frac{t}{2} = 1$ $=>t/2=1$

$:.t=2$

How do you solve 5^(-t/2)=0.205−t2=0.205^(-t/2)=0.20?