Posted by Mindy on Monday, October 4, 2010 at 9:24pm.
The side of a rhombus is 15 centimeters long, and the length of its longer diagonal is 24.6 centimeters. Find the area.

PreCalculus  Reiny, Monday, October 4, 2010 at 11:07pm
The diagonals in a rhombus rightbisect each other, giving you 4 identical rightangled triangles
look at one of them, the hypotenuse would be 15 and the other side is 12.3 , half the diagonal given.
Can you find the missing side using Pythagoras?
Find the area of one of the triangles , then multiply by 4 
PreCalculus  Albert, Saturday, December 11, 2010 at 10:49pm
211.6 units squared