Answer:
equiangular -right -obtuse -acute.
Yes, considering that the ball cannot have two different heights at the same exact time.
The third option: uses visual representation of the logical...
For #16, it can be assume that the two angles are linear, so set them both equal to 90 (9x+x-10=90) and solve for x. Once you have x, plug it into the equations to find the measure of both angles. If both your final answers are added, they should equal 180. If not, go back and try to find where you messed up.
