You can put this solution on YOUR website! show the work to solve:
r = 2/((5L)^-1/2)
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r is solved for.
That wasn't hard.
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You didn't say what you want to solve for. If it's L:
r = 2/((5L)^-1/2)
((5L)^-1/2) = 2/r
((5L)^1/2) = r/2