Geo_Book_Answers

USING YOUR ALGEBRA SKILLS 1
1. (3, 4)
2. (9, 1.5)
3. (5.5, 5.5)
4. (6, 44)
5. Yes. The coordinates of the midpoint of a
segment with endpoints (a, b) and (c, d) are found
a c
by taking the average of the x-coordinates, , 2
b d
and the average of the y-coordinates, .Thus 2 the
a c b d
midpoint is , . 2 2
6. (3, 2) and (6, 4). To get the first point of
trisection, sum the coordinates of points A and B
to get (9, 6), then multiply those coordinates by 1
3 to
get (3, 2). To get the second point of trisection, sum
the coordinates of points A and B to get (9, 6), then
multiply those coordinates by 2
3 to get (6, 4). This
works because the coordinates of the first point
are (0, 0).
7. Find the midpoint, then find the midpoint of
each half.
8a. Midpoints for Figure 1 are (5.5, 6.5); for
Figure 2, (16, 6.75); and for Figure 3, (29.75, 5.5).
8b. For these figures the midpoints of the two
diagonals are the same point.
ANSWERS TO EXERCISES 9
Answers to Exercises