Angle Sums and the 15-75-90 Right Triangle

The Angle Sum Rectangle

Study the rectangle below and be certain you understand where each of the trigonometric expressions comes from.[br][br]How would the expression change if AF=1?[br]How would the expression change if EF=1?

15-75-90 Special Right Triangle

Apply your side-chasing skills and the angle sum rectangle above to find the exact lengths of the missing triangle side lengths below.[br][br]Based on this, devise a 15-75-90 Special Right Triangle rule.

Information: Angle Sums and the 15-75-90 Right Triangle