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Recall the classification of quadrilaterals. You can begin by finding the slopes of the sides.
Parallelogram
Let's plot the given points on a coordinate plane and graph the quadrilateral.
Quadrilateral | Definition |
---|---|
Parallelogram | Both pairs of opposite sides are parallel |
Rhombus | Parallelogram with four congruent sides |
Square | Parallelogram with four congruent sides and four right angles |
Trapezoid | Quadrilateral with exactly one pair of parallel sides |
Let's first find the side's slopes using the Slope Formula.
Side | Slope Formula | Simplified |
---|---|---|
Slope of AB: ( - 1,4), ( 2,6) | 6- 4/2-( - 1) | 2/3 |
Slope of BC: ( 2,6), ( 3, 3) | 3- 6/3- 2 | - 3 |
Slope of CD: ( 3,3), ( 0,1) | 1- 3/0- 3 | 2/3 |
Slope of DA: ( 0,1), ( - 1,4) | 4- 1/- 1- 0 | - 3 |
We can tell that the slopes of the opposite sides of our quadrilateral are equal. Therefore, both pairs of opposite sides are parallel and the quadrilateral is therefore a parallelogram. We can also tell that the consecutive side are not perpendicular, as their slopes are not opposite reciprocals. - 3 (2/3) ≠-1 Therefore, our quadrilateral is either a parallelogram or a rhombus. To check, we can find the lengths of its sides using the Distance Formula.
Side | Distance Formula | Simplified |
---|---|---|
Length of AB: ( - 1,4), ( 2,6) | sqrt(( 2-( - 1))^2+( 6- 4)^2) | sqrt(13) |
Length of BC: ( 2,6), ( 3,3) | sqrt(( 3- 2)^2+( 3- 6)^2) | sqrt(10) |
Length of CD: ( 3,3), ( 0,1) | sqrt(( 0- 3)^2+( 1- 3)^2) | sqrt(13) |
Length of DA: ( 0,1), ( - 1,4) | sqrt(( - 1- 0)^2+( 4- 1)^2) | sqrt(10) |
Our parallelogram has two pairs of congruent sides. Therefore, the most specific term for this quadrilateral is a parallelogram.