Once you draw the altitude CD as C to AB you should form a 30, 60, 90 Right Triangle.
You can use the Trig Functions Sine, Cosine, and Tangent and their relationship to the sides of a Right Triangle to calculate AC.
Remember in the Right Triangle you form, the side opposite the right angle, 90°, is the longest side (hypotenuse).
Look carefully at your diagram to see if AC is the hypotenuse
Label your sides and give it a try
I got 10 or e
By the way do you have a diagram that you can upload? That would be useful so we are looking at the same thing.
You can also review the general relationship between the sides in a 30, 60, 90 Right Triangle and ratio them to CD. Side opposite the 30° angle is the shortest side, the side opposite the 60° angle is shortest side times √3 and the side opposite the 90° angle is 2 times the shortest side.
I hope you find this useful.
If you have any questions, please send me a message.
