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Constructions. Centoids. Review of Prerquisite. To construct a perpendicular bisector you need a . Fish . Let’s begin !. Medians. A Median is a segment connecting the vertex of a triangle to the opposite midpoint.
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Constructions Centoids
Review of Prerquisite To construct a perpendicular bisector you need a ... Fish. Let’s begin !
Medians A Median is a segment connecting the vertex of a triangle to the opposite midpoint.
The medians of a triangle are concurrent at a point called the centroid.
Construction of the Median Start with the FISH to find a midpoint of side BC. Start with the base and point B.
Construct arc from point C past the midpoint of BC Connect the arc intersection points to find the midpoint. Construct the median from A to the midpoint.
Construct arc from point A past the midpoint of BA Connect the arc intersection points to find the midpoint. Construct the median from C to the midpoint.
It is not necessary to construct all three medians because… Two intersecting lines determine a point. Centroid
It is only necessary to draw 2 medians. The third median would only intersect the other lines at the same point. We will now look at several examples of centroids to solidify your understanding.
1 3 2 4
Construction of the Median Start with the FISH to find a midpoint of side BC. Start with the base and point B.
Construct arc from point C past the midpoint of BC Connect the arc intersection points to find the midpoint. Construct the median from A to the midpoint.
Construct arc from point A past the midpoint of BA Connect the arc intersection points to find the midpoint. Construct the median from C to the midpoint.
It is not necessary to construct all three medians because… Two intersecting lines determine a point. Centroid
When two medians intersect then they divide each other into a small segment and a large segment. Let’s look at several situations.
The ratio is always 2:1 Therefore… 10 If DF = 5, then AD = _____ ? 5
10 If DF = 5, then AD = _____ ? 7
6 If AD = 12, then DF = _____ 12 ?
8 If AD = 16, then DF = _____ 16 ?
Summary 1. A Median is a segment connecting the vertex of a triangle to the opposite midpoint. 2. The three medians of a triangle are concurrent. 3. The point of concurrency is called a centroid.
Summary 4. When two medians intersect then they divide each other into a large segment and a small segment.
Summary 5. The centroid is always inside the triangle. 6. To construct the median you… You construct a fish on 2 sides. You connect the opposite vertex to the midpoint.
C’est fini. Good day and good luck. That’s all folks. A Senior Citizen Production