The equation for the area of a rhombus is [tex]A = \frac{ (d_1)( d_2)}{2} [/tex], where [tex]d_1[/tex] and [tex]d_2[/tex] are the length of the diagonals of the rhombus, and A = area of the rhombus.
Your two diagonals are:
[tex]d_1[/tex] = 5m + 5m = 10m
[tex]d_2[/tex] = 10m + 10m = 20m
Plug these values into the equation for the area of a rhombus:
[tex]A = \frac{ (d_1)( d_2)}{2} \\
A = \frac{ (10)(20)}{2} \\
A = \frac{200}{2} \\
A = 100m^2[/tex]
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Answer: 100 [tex] m^{2} [/tex]