Basics

Question 1

Segment Addition Postulate

Answer 1

Given point C on segment AB,
Then
AC + CB = AB

Question 2

Angle Addition Postulate

Answer 2

Given point C such that it is between the rays of angle AVB,
Then
AVC + VCB = AVB

Question 3

Point

Answer 3

A place in space with no dimension

Question 4

Line

Answer 4

A one dimensional, 0 thickness, collection of infinitely many points that extends in opposite directions forever

Question 5

Plane

Answer 5

A flat, 2 dimensional, surface that extends forever

Question 6

Ray

Answer 6

An infinite collection of points, in 1 dimension, that has a start point and extends in one direction forever

Question 7

Given segment AB with midpoint M and AM = 2x + 12 and MB = 3x + 6, find AB.

Answer 7

Step 1) Set equations equal to each other
AM = MB
Step 2) Substitute equations 
2x + 12 = 3x + 6
Step 3) Combine like terms
2x + 12 - 2x - 6 = 3x + 6 - 2x - 6
6 = x
Step 4) Back substitute to solve for AM
AM = 2x + 12 = 2(4) + 12
AM = 20
Step 5) Find MB
Since AM = MB, then MB = 20
Step 6) Substitute to find AB
AB = AM + MB, by Segment Addition Postulate 
Then, AB = 20 + 20 = 40