Answer:
see the attachments for the graph, and a spreadsheet with midpoints and slopes
Explanation:
We are given the coordinates of the vertices of a triangle, and asked to find the parameters of the perpendicular bisectors of the sides of the triangle. The perpendicular bisectors are to be plotted on the graph.
Given:
Coordinates A(1, 6), B(5, 4), C(5, -2)
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Find:
a) Graph and label the triangle
b) Find the midpoint of each side of the triangle
c) Find the slope of each side of the triangle
d) Find the slope of each perpendicular bisector
e) Use the midpoint and the perpendicular slope to accurately draw each perpendicular bisector on the triangle
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Solution:
a)
See the attached graph for shaded triangle ABC.
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b)
The midpoint (M) of a segment AB will be ...
M = (A+B)/2
For example, the midpoint of segment AB is ...
D = ((1, 6) +(5, 4))/2 = (1+5, 6+4)/2 = (6, 10)/2 = (3, 5)
This repetitive arithmetic is carried out in the spreadsheet shown in the second attachment. The midpoints are ...
D(3, 5) is midpoint of AB
E(5, 1) is midpoint of BC
F(3, 2) is midpoint of CA
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c)
The slope of a segment is found using the slope formula (or by counting grid squares). That formula is ...
m = (y2 -y1)/(x2 -x1)
For segment AB, this is ...
mAB = (4 -6)/(5 -1) = -2/4 = -1/2
The other slopes are calculated similarly in the spreadsheet. When the denominator is zero (a vertical line), the slope is "undefined."
mBC = undefined
mCA = -2
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d)
The slope of the perpendicular line is the opposite reciprocal of the slope of the segment.
m⟂AB = -1/(-1/2) = 2
m⟂BC = 0 . . . . . a horizontal line has 0 slope
m⟂CA = -1/-2 = 1/2
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e)
The perpendicular bisectors of each of the sides of the triangle are shown in the first attachment. As the lesson title indicates, their point of concurrency is G(1, 1), the circumcenter of the triangle.