Suppose a triangle has two sides of length 3 and 4 and that the angle between these two sides is 60. what is the length of the third side of the triangle ?

You would take three squared plus four squared and get whatever number and then take the square root of that (aka Pythagorean theorem) 

so it would end up being 9 plus 16 equals 25 then take the square root of 25 which is 5. so 5 is the other side.

I think it is 7 I did this in 7th grade but it is confusing

(-8,5) bu tun not sure ok