A parallelogram has sides with lengths of 14 and 8. If the parallelogram's area is 84, what is the length of its longest diagonal?

1 Answer
May 16, 2016

The longest diagonal =20.203

Explanation:

The parallelogram with sides a,b has an area computed as
A=a×b×sin(θ)=84
Solving for θ we obtain θ0=2.29353[rad]
Associating now an oriented segment to each side we get
a=a{cos(θ0),sin(θ0)},b=b{1,0}
The two diagonals are obtained as
d1=a+b
d2=ab
Computing their length we get
d1=10.5753
d2=20.203