Bellwork (Don’t forget to get your materials out!)

1) What is the length of the caterpillar in cm?

2) You are put in charge of the scoreboard for your home football games. Your team has the ball on its own 33 yard line. It needs 14 yards for a first down. On the play the quarterback is sacked at the 28 yard line. How many yards did the team lose on the play? What will you enter into the scoreboard for “Yards to Go”?

Section 1-2 Part A:Measuring Segments

Rigor: Calculate the measure of segments using postulates, midpoints, and congruency

Relevance: Measuring segments allows us to describe and calculate length and distance

• The numbers are called coordinates

• The distance along a line is UNDEFINED until a UNIT is chosen!

• Distance is always POSITIVE. If you get a negative number, take the absolute value.

AB = |a – b| or |b - a|A

a

B

b

EX 1: Calculate the length of each segment.

B) XY = ?A) AB = ?

EX 2: Calculate NO.

Congruent SegmentsCongruent segments are segments that have the same length. In the diagram, PQ = RS, so you can write PQ RS. This is read as “segment PQ is congruent to segment RS.” Tick marks are used in a figure to show congruent segments.

EX 3: Real Life Application• Recall that a midpoint is the

exact middle of a segment.

EX: The map shows the route for a race. You are 365m from drink station R and 2km from drink station S. The first-aid station is located at the midpoint of the two drink stations. How far are you from the first-aid station?

EX 4: Using a Midpoint

D FE 4x + 6 7x – 9

D is the midpoint of EF, ED = 4x + 6, and DF = 7x – 9. Find ED, DF, and EF.

CW 1-2 Part A• This is only half of section 1-2, so this is only worth 5 points.

The other half of the CW will be assigned during the next class.

• This comes from the TEXTBOOK, not the Core book, so you will need a piece of paper to write on.

• Heading: Section 1-2 CW part A

• Assignment: textbook pg 17 – 18 #7, 8, 16, 18, 33

• NO WORK = NO CREDIT