Mini Lesson 7.9c

ASB Math Week 3 Practice

Topics:

• Median of a Triangle

• Midsegment (Triangles + Trapezoids)

Median of a Triangle

Definition

A line segment drawn from a vertex to the midpoint of the opposite side of the vertex.

Fill in the Blanks

EXAMPLE: In $\Delta PQR$ , $\overline{RS}$ is a median. If $PQ=7$ inches, find PS.

Fill in the Blanks

YOU TRY: In $\Delta ABC$ , $\overline{AD}$ and $\overline{CE}$ are medians. If AE = 6 feet and BC = 14 feet, determine BE and CD.

Median of a Triangle

Centroid

• The point that all medians of a triangle intersect inside the triangle.

• Cuts a median in a ratio of 2:1.

Fill in the Blanks

EXAMPLE: In $\Delta PQR$ , $\overline{PS}$ and $\overline{QT}$ are medians. Find TG if GQ = 17 inches.

Fill in the Blanks

YOU TRY: In $\Delta JKL$ , $\overline{JM}$ and $\overline{LN}$ are medians. Determine LG if GN = 1 yard.

Midsegment of a Triangle

Definition

Fill in the Blanks

EXAMPLE: In $\Delta CAD$ , $\overline{BE}$ is a midsegment. Find CD.

Fill in the Blanks

YOU TRY: In $\Delta PQT$ , $\overline{RS}$ is a midsegment. Find PQ.

Midsegment of a Trapezoid

Definition

Fill in the Blanks

EXAMPLE: In trapezoid $PART$ , $\overline{MD}$ is a midsegment. Find MD.

Fill in the Blanks

YOU TRY: In trapezoid $PART$ , $\overline{MD}$ is a midsegment. Find RT.