6­5 Conditions of Special Parallelograms
If any of these are true, we have a rectangle:
- A parallelogram with at least one right angle
- A parallelogram with diagonals congruent
If any of these are true, we have a rhombus:
- A parallelogram with one pair of consecutive sides congruent
- A parallelogram with diagonals perpendicular
- A parallelogram with diagonals bisecting angles
As a class: Page 422, #1
Given: AC
B
C
A
D
BD
Conclusion: ABCD is a rectangle
Given: AB || CD, AB
T
CD, AB T BC
Conclusion: ABCD is a rectangle
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P(-5, 2), Q(4, 5), R(6, -1), S(-3, -4)
What type of parallelogram do we
have?
W(-6, 0), X(1, 4), Y(2, -4), Z(-5, -8)
What type of parallelogram do we
have?
2