Question

Two opposite sides of a parallelogram each have a length of `4`. If one corner of the parallelogram has an angle of `(3 pi)/4` and the parallelogram's area is `80`, how long are the other two sides?

Answer 1

`b=28.28`

Explanation:

Area of the parallelogram is `=ab sin theta` where `a=4` is the side and `theta=(3pi)/4` and we have to find `b=?`
Therefore
Area`=80=4b sin((3pi)/4)`
or
`bsin((3pi)/4)=80/4`
or
`b(0.707)=20`
or
`b=28.28`