Hi everyone. Let me start by saying that my math is quite rusty to say the least. I got through high school math through memorizing formulas and as a result I have large, gaping holes in my understanding of mathematics and I'm trying desperately to make up for it. This is especially true for my knowledge of geometry and parts of trigonometry. Take a look at this math problem page I found on Google: http://www.coastal.edu/math/mathcontest/Level1_04.pdf. See number 3? How do you solve this problem? I have no clue where to begin. I don't remember the strategies. I have the same issue with number 7. Number 10 is a mystery as well (notice these all have to do with angles and triangles...). Exactly what kind of math is used to solve those problems? Is it straight geometry? Trigonometry? General precalculus? And do you know of any good books I can use to teach myself these things? I am looking for a regular math book, not a scholastic textbook used in a classroom. I have also seen some SAT test questions involving angles like this and I am stumped on them too. I do not need help remembering what a logarithm is or how to factor quadratic equations--I remember all that and find it extremely easy. I am just stumped on the types of problems mentioned above. If you know of some good books or a strategy I should follow then I would greatly appreciate your help. The fact that I cannot solve these problems but at one time successfully completed a calculus course (with an A) is very depressing. It literally keeps me up at night. Thankyou in advance to anyone that replies.