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1.2 – Linear Measure & Precision Unlike a line, a line segment, or segment, can be measured because it has two endpoints. A segment with endpoints A and B can be named as AB or BA . The measure of AB is written as AB. Recall that for any two real numbers a and b, there is a real number n between a and b such that a n b . This relationship also applies to points on a line and is called betweenness of points. Point M is between points P and Q if and only if P, Q and M are collinear and PM MQ PQ . Notice that points R and T are not between points P and Q. Example 1 a. Find LM. b. Find XZ. c. Find x and ST if T is between S and U, ST 7 x , SU 45 , and TU 5x 3 . When segments have the same measure, they are said to be congruent. KEY CONCEPT – Congruent Segments Words Two segments having the same measure are congruent Symbol is read is congruent to. Red slashes on the figure also indicate that segments are congruent. L2 – pg 18 (22-33) Model XY PQ