Saturday
May 18, 2013

# Homework Help: math

Posted by shan on Saturday, September 6, 2008 at 2:19pm.

the diagonals of a parellelogram are 20 cm and 30cm long and intersect at an angle of 25 degrees. Find the sides of the parellelogram

• math - Reiny, Saturday, September 6, 2008 at 3:42pm

the diagonals intersect each other so let's consider the triangle of sides 15 and 10 with the contained angle of 25 degrees
by the cosine law you can find the third side, which will be one of the sides of the parallelogram.

x^2 = 15^2 + 10^2 - 2(15)(10)cos 25
= 53.10766

x = 7.28

Do the same with the other side by using sides 15, 10 and angle 155

Related Questions

Trig-Algebra help asap - The adjacent sides of a parallelogram measure 8 cm and ...
Trig - The diagonals of a parallelogram intersect at a 42&#9702; angle and ...
math - What polygon has 20 diagonals?I don't know how to figur this out. ...
Pre-calculus - Find the lengths of the diagonals of a parallelogram with ...
Geometry - The diagonals of a rectangle are 12 inches long and intersect at an ...
geometry - the diagonals of a rectangle are 12 inches long and intersect at an ...
pre calculus - A parallelogram has a 70 degree angle and sides 6 cm and 10 cm ...
geometry - A rectangle is 80 cm long and 20 cm wide. Find, to the nearest degree...
geometry - a rectangle is 80 cm long and 20 cm wide. find, to the nearest degree...
geometry - 1. An exterior angle of a regular polygon measures 30 degrees. What ...