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Answer the following
problems dealing with
Coordinate Geometry proofs.
(Please Note: Answers will show only ONE
possible solution to a problem.
Even when a specific method of solution is requested, answers may vary in
presentation.)
Before you
begin, refresh your memory ...
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When developing a coordinate
geometry proof:
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1. draw and label the graph |
| 2. state the formulas you
will be using |
| 3. show ALL work (if
you are using your graphing calculator, be sure to show your screen displays
as part of your work.) |
4. have a concluding
sentence stating
what you have proven and why it is true. |
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1. |
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Prove that quadrilateral A(1,2),
B(2,5), C(5,7) and D(4,4) is a
parallelogram by using slopes. |
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Proof
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2. |
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Prove that A(1,1),
B(4,4), C(6,2) are the vertices of a
right triangle. |
Proof
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3. |
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Prove that quadrilateral A(1,-2),
B(13,4),
C(6,8) and D(-2,4) is a
trapezoid, but is NOT an isosceles trapezoid. |
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Proof
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4. |
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Prove that A(-2,2),
B(1,4), C(2,8) and D(-1,6) is a
parallelogram using midpoints. |
Proof
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5. |
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Prove that A(-3,2),
B(-2,6), C(2,7)
and D(1,3) is a
rhombus. |
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Proof
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6. |
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Prove that A(4,-1),
B(5,6), C(1,3) is an isosceles right
triangle. |
Proof
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7. |
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Guinevere and Lancelot see a drawing
of quadrilateral ABCD, A(2,2),
B(5,-2),
C(9,1) and D(6,5).
Guinevere says the figure is a rhombus, but not a
square. Lancelot says the figure is a square.
Write a proof to show who is making the correct
observation. |
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Proof
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