1.3 Measuring Segments and Angles

Postulate 1-5Ruler Postulate The distance between any two points is the absolute value of the difference of the corresponding numbers (on a number line or ruler) Congruent Segments: two segments with the same length Congruent Symbol:

Postulate 1-6Segment Addition Postulate If three points A, B, and C are collinear and B is between A and C, then AB + BC = AC A B C

Using the Segment Addition Postulate If DT = 60, find the value of x. Then find DS and ST. So if… and Then… DST 2x - 83x - 12

Using the Segment Addition Postulate If EG = 100, find the value of x. Then find EF and FG. EFG 4x - 202x + 30

Midpoint: a point that divides the segment into two equal parts ABC B is the midpoint, so AB = BC Note: any point line or ray that goes through the midpoint of a segment is called a segment bisector

Finding Lengths C is the midpoint of AB. Find AC, CB, and AB. A CB 2x + 1 3x – 4

Z is the midpoint of XY, and XY = 27. Find XZ. Meaning Z is HALF the distance of XY so… X ZY 27