# Math Help - just checking

1. ## just checking

ok i finished the problem but i want 2 know what u got...

the sides of a parallelogram are 4.0cm and 6.0cm. One angle is 58 degrees while another is 122 degrees. Find the lengths of the diagonals of the parallelogram.

I got one diagonal as 5.2 and the other as 8.8

2. ## The

Originally Posted by veronica mars
ok i finished the problem but i want 2 know what u got...

the sides of a parallelogram are 4.0cm and 6.0cm. One angle is 58 degrees while another is 122 degrees. Find the lengths of the diagonals of the parallelogram.

I got one diagonal as 5.2 and the other as 8.8
answer should be 7.211...did you figure out it was a right triangle?

3. ## no....

Originally Posted by Mathstud28
answer should be 7.211...did you figure out it was a right triangle?
i just did the formula u gave me for the other problem with the two angles to find the lengths of the diagonals

4. ## Yes

Originally Posted by veronica mars
i just did the formula u gave me for the other problem with the two angles to find the lengths of the diagonals
but did you realize that the $\theta$ we are using in this case is $180-\frac{122}{2}-\frac{58}{2}=90$ in which case the formula I gave you reverts back to the pythagorean theorem since the $cos(90)=0$ elminating the last term

5. Originally Posted by Mathstud28
but did you realize that the $\theta$ we are using in this case is $180-\frac{122}{2}-\frac{58}{2}=90$ in which case the formula I gave you reverts back to the pythagorean theorem since the $cos(90)=0$ elminating the last term
no. now i am even more confused than i already was, but its ok. im getting this whole assignment wrong anyways its the beginning of the quarter. i will be able to bounce back.