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11. What is the midpoint of CD?

12. a. What are the exact lengths of
segments AB and CD?
b. How do the lengths of AB and CD
compare?
c. Is the following statement true or
false?
AB=CD

11. What is the midpoint of CD? 12. a. What are the exact lengths of segments AB and-example-1
User Valentasm
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1 Answer

25 votes
25 votes

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Answer:

11. (-1.5, 3)

12. √29, identical lengths, true they are congruent

Explanation:

11. The midpoint is halfway between the end points. On a graph, you can count the grid squares between the ends of the segment and locate the point that is half that number from either end.

Points C and D differ by 2 in the y-direction, so the midpoint will be 1 unit vertically different from either C or D. That is, it will lie on the line y = 3. The segment CD intersects y=3 at x = -1.5, so the midpoint of CD is (-1.5, 3).

If you like, you can calculate the midpoint as the average of the end points:

midpoint CD = (C +D)/2 = ((-4, 4) +(1, 2))/2 = (-3, 6)/2 = (-1.5, 3)

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12. The exact length can be found using the Pythagorean theorem. The segment is the hypotenuse of a right triangle whose legs are the differences in x- and y-coordinates.

In the previous problem, we observed that the y-coordinates of C and D differed by 2. The x-coordinates differ by 5. Looking at segment AB, we see the same differences: x-coordinates differ by 5 and y-coordinates differ by 2. Then the lengths of each of these segments is ...

AB = CD = √(2² +5²) = √29

a) The exact lengths of segments AB and CD are √29 units.

b) The lengths of the segments are identical

c) It is TRUE that the segments are congruent.

User Ekansh
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2.9k points