Question

A rectangle has a diagonal of 18cm. The diagonal creates a 60 degree angle at the base of the triangle. Write an exact expression for the base and the height of the triangle.

Answer 1

I'm a little rusty, but here goes...

In your triangle , call your base b & your height h, the hypotenuse would be 18 & the base angle is 60°
so sin60° = h/18 ---> h = 18sin60
cos60° = b/18 ---> b = 18cos60

So, later when you need area a = b*h