The definition of an angle uses the undefined term .

a. line
b. point
c. plane
d. ray

Point.

This is one of the classic problems of Euclidean geometry.

The angle is determined by three points, we call it A, B, C, with A ≠ C and B ≠ C.

We denote an angle with three points and a symbol ∠.  The middle point is always the vertex.  We can also give angle names only with vertices. For example, based on the attached image, the angle can be denoted as ∠BAC, or ∠CAB, or ∠A.

Types of Angles  

Note:

Undefined terms are the basic figure that is not defined in terms of other figures. The undefined terms (or primitive terms) in geometry are a point, line, and plane.

These key terms cannot be mathematically defined using other known words.

Keywords: the definition of an angle, the undefined term, line, point, line, plane, ray, endpoint, acute, obtuse, right, straight, Euclidean geometry

she played for 18.75 hours.

step-by-step explanation:

if she played 2/4 of a hour on tuesday. and there is 60 minutes in an hour and 60 divided by 4 is 7.5. and she played 2/4 of an hour on thursday then again 60 divided by 4 is 7.5, you add 7.5+7.5=56.25. now you have to do 1/4 of an hour, it equals 3.75. now you have to add them all up. 3.75+7.5+7.5=18.75

i hope this and i hope you get it right. it took me a while to get this done for you. : )