6. Trapezoids and Kites
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A quadrilateral is a trapezoid if it has exactly one pair of parallel sides.
ABCD is a trapezoid.
To verify that our quadrilateral is a trapezoid, we have to check if our quadrilateral has exactly one pair of parallel sides. To do this, let's find the slope of each side using the Slope Formula.
| Side | Slope Formula | Simplified |
|---|---|---|
| Slope of AB: ( -4,-1), ( -2,3) | 3-( -1)/-2-( -4) | 2 |
| Slope of BC: ( - 2,3), ( 3, 3) | 3- 3/3-( -2) | 0 |
| Slope of CD: ( 3,3), ( 5, - 1) | - 1- 3/5- 3 | - 2 |
| Slope of DA: ( 5, - 1), ( - 4,- 1) | -1-( - 1)/-4- 5 | 0 |
We can see that the slopes of AB and CD are not equal, so these sides are not parallel. The slopes of BC and DA are equal, so these sides are parallel. Since our quadrilateral has exactly one pair of parallel sides, it is a trapezoid.