Answer:
area= l×b or b^2 or l^2 = 16900
to get one side length of the square take root of area i.e

=130 cm is length of the base
It means multiply by the reciprocal of the number. The reciprocal is 1 divided by the number (x).
So assuming you're number is 3, the reciprocal of 3 would be 1/3.
or
Assuming the number is 0.2, the reciprocal of the number would be 1/0.2