Posted by Jamilla on .
Find the lengths of the diagonals of a parallelogram with adjacent sides of 12cm and 13 cm if the angle between the sides is 50 degrees.
The shorter diagonal is what in terms of cm?
The longer diagonal is what in terms of cm?

Precalculus 
Reiny,
Use cosine law
(shortone)^2 = 12^2 + 13^2  2(12)(13)cos50°
etc
for the longone, replace the end part with cos130°