## anonymous one year ago The point (3, -4) is on the terminal side of an angle θ . What is cos θ?

1. misty1212

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2. misty1212

find the hypotenuse of that right triangle, lets call it $$h$$ it will be $$\cos(\theta)=\frac{3}{h}$$

3. misty1212

the hypotenuse you can do with your eyeballs if you remember the mother of all right triangles, the 3 - 4 - 5 right triangle or you could use pythagoras if you do not remember that one

4. anonymous

Through high school ive had sucky math teachers, so i barely learned anything. So, im having to take online classes and im a visual learner and dont know how to do any of this. Its so confusing

5. misty1212

what you need to know for this is that the cosine is the first coordinate divided by the length of the hypotenuse

6. misty1212

you are told that the first coordinate is 3 so that is your numerator also the other leg of the triangle has length 4 that means, by pythangoras, since $3^2+4^2=h^2$ you have $9+16=h^2\\ 25=h^2\\ 5=h$

7. anonymous

here are the answer choices a) - 3/5 b) 3/5 c) -3/4 D) 3/4 E) 3

8. misty1212

ok which one is it?

9. anonymous

b

10. misty1212

yes