The equation for the area of a rhombus is

, where

and

are the length of the diagonals of the rhombus, and A = area of the rhombus.
Your two diagonals are:

= 5m + 5m = 10m

= 10m + 10m = 20m
Plug these values into the equation for the area of a rhombus:

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Answer: 100
