Hi I need help with special right triangles

Question

The length of the side opposite the 30° angle of a 30°-60°90° special right triangle is 18ft. Determine the lengths of the other two sides.

Also, can you help me how to find the adjacent and opposite of a triangle since I'm struggling a lot with that Please and Thank You

Answer 1

Hi Charlie. "SOH CAH TOA" - The sine gives the proportion of the opposite side to the hypotenuse, the cosine gives the proportion of the adjacent to the hypotenuse, and the tangent gives the proportion of the opposite to the adjacent. And sin(30 degrees) is 1/2 as you can check on a calculator. That means that that 18ft is half the length of the hypotenuse. The cosine of 30 degrees is sqrt(3)/2. Can you figure out what this means for the length of the side adjacent to the 30 degree angle now?