posted by Jamilla .
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?
Use cosine law
(shortone)^2 = 12^2 + 13^2 - 2(12)(13)cos50°
for the longone, replace the end part with cos130°