# area of triangles 2

#### Tessarina

a rhombus has an area of 50 cm^2 and an internal angle of size 63 degrees. Find the lenth of its sides.

#### skeeter

MHF Helper
a rhombus has an area of 50 cm^2 and an internal angle of size 63 degrees. Find the lenth of its sides.

... use the parallelogram area formula provided in your previous post.

#### Tessarina

i worked out the other one, but with this one i just can't seem to get the right answer.

i think iam doing something wrong,

#### skeeter

MHF Helper
i worked out the other one, but with this one i just can't seem to get the right answer.

i think iam doing something wrong,
can't fix it if we don't know what you tried ...

#### Tessarina

could you just show me what working out you would do?

#### Prove It

MHF Helper
Try using the formula

$$\displaystyle A = ab\sin{\theta}$$.

Like Skeeter said, show us what working you have done. We are not here to do your work for you.

#### Tessarina

this is the working out i did:

A= 50cm^2

1/2 x a x c x sin63= 50

acsin63= 100

-and thats all i got to.

#### Prove It

MHF Helper
this is the working out i did:

A= 50cm^2

1/2 x a x c x sin63= 50

acsin63= 100

-and thats all i got to.
You're almost there. Just remember that in a rhombus, all sides are equal.

#### Tessarina

then do i work it out by going--
2asin63=100
2a=100/sin63
2a=112.23
a=56.11

but then if i double that to get the area of the whole rhombus i get
112.23

what am i doing wrong?

#### Prove It

MHF Helper
then do i work it out by going--
2asin63=100
2a=100/sin63
2a=112.23
a=56.11

but then if i double that to get the area of the whole rhombus i get
112.23

$$\displaystyle a^2\sin{\theta} = 100$$.