Posted by Aria on .
what is the area of a rhombus with a 60 degree angle and sides 5 cm long? (round to the nearest 10th)

geometry 
Jai,
recall that the area of rhombus is just
A = b*h
where b = base and h = height
we already have the base, which is 5 cm. we need to find for the height,, to get this, observe that if we draw the rhombus and draw a broken line representing the height, we see that a right triangle is form, particularly, a 306090 triangle
to get height,
5 * sin 60 = 4.33 cm
**note that we use sin 60 here because 80 degrees is the opposite angle of the height
substituting:
A = b*h
A = 5*(4.33)
A = 21.65 sq cm
hope this helps~ :)