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WARM UP March 11, 2014. Solve for x Solve for y . x º. 3x º. (40 + y)°. 28°. EOCT Week 9 #2. Medians of a Triangle. The MEDIANS of a triangle join the vertex of one angle to the opposite side’s midpoint. Every Triangle has 3 Medians.
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WARM UP March 11, 2014 • Solve for x • Solve for y xº 3xº (40 + y)° 28°
Medians of a Triangle The MEDIANS of a triangle join the vertex of one angle to the opposite side’s midpoint. Every Triangle has 3 Medians.
Centroid Theorem The length of the segment from the vertex to the centroid is twice the length of the segment from the centroid to the midpoint. 2x x
C How much is CW? CW = 2(WF) D CW = 2(13) E W 13 B A F CW = 26
C How much is WD? AW = 2(WD) D 18 = 2(WD) E W 18 B A F 9 = WD
How do you find the Centroid Given 3 points? Remember the midpoint formula , ) The Centroid Formula is very similar. , )
Example Find the centroid of a triangle whose vertices are (-1, -3), (2, 1) and (8, -4).
You Try!! Find the centroid of a triangle whose vertices are A(4, -1), B(2, 6), and C(9, -5).
YOU TRY!!!! In ABC, AN, BP, and CM are medians. If EN = 12, find AN. C N AE = 2(12)=24 P E B AN = AE + EN M A AN = 24 + 12 AN = 36
Mid-Segment of a Triangle The MID-SEGMENT of a triangle is a segment that joins two midpoints of two sides of a triangle.
The mid-segment of a triangle joins the midpoints of two sides of a triangle such that its length is half the length of the third side of the triangle.
Triangle Proportionality Theorem If a line is parallel to one side of the triangle and it intersects the other two sides, then the line divides the other two sides proportionally.
Examples Solve for x. 9 = 3x 3 = x
YOU TRY!! Solve for x.