Posted by leo on .
The base of a right prism is a rhombus whose sides are 20cm and the shorter diagonal is 24in..find the area pls.

solid mensuration 
Reiny,
The diagonals of a rhombus bisect each other at right angles.
You should see 4 identical rightangled triangles
let the missing side in each of those triangles be x
x^2 + 12^2 = 20^2
x = 16
So the longer diagonal is 32
Area of rhomus = (1/2)(product of diagonals)
= ... 
solid mensuration 
leo,
where did u get the 12?because the sides are centimeter and the other diagonal is inches?

solid mensuration 
Reiny,
Didn't notice that.
Weird that they would mix units like that.
Anyway,
1 inch = 2.54 cm
As I said, the diameters rightbisect each other, so what is 1/2 of 24 ?
So change the 12 inches to cm
= 12(2.54) cm
= 30.48 cm
Now everything is in the same units.