McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
4. Parallel Lines and Proportional Parts
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Exercise 42 Page 580

Graph:

Coordinates: (-4,4) and (-0.5,6)
Explanation: see solution.

Practice makes perfect

Let's begin with drawing â–ł ABC using the given points.

Now, we will recall the Triangle Midsegment Theorem.

Triangle Midsegment Theorem

A midsegment of a triangle is parallel to one side of the triangle, and its length is one half the length of that side

This means that to find the midsegment of â–ł ABC we should find the midpoints of AB and AC. To do this, we will use the Midpoint Formula. The midpoint O between two points M(x_1,y_1) and N(x_2,y_2) has the following coordinates. O(x_1+x_2/2,y_1+y_2/2) Let's start with evaluating the midpoint of AB. To do this, let's substitute ( -8, 7) and ( 0,1) into the above formula.
(x_1+x_2/2,y_1+y_2/2)
(-8+ 0/2,7+1/2)
(-8/2,8/2)
(-4,4)
The midpoint of AB has coordinates of (-4,4). Now, we will do the same to evaluate the midpoint of AC. Let's substitute ( -8, 7) and ( 7,5) into the Midpoint Formula.
(x_1+x_2/2,y_1+y_2/2)
(-8+ 7/2,7+5/2)
(-1/2,12/2)
(-0.5,6)
The midpoint of AC has coordinates of (-0.5,6). Therefore, by the Triangle Midsegment Theorem, the coordinates of the midsegment of â–ł ABC that is parallel to BC are (-4,4) and (-0.5,6).