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Recall the classification of quadrilaterals. You can begin by finding the slopes of the sides.
Rhombus
Let's plot the given points on a coordinate plane and graph the quadrilateral.
To determine the most precise name for our quadrilateral, let's review the classification of quadrilaterals.
| Quadrilateral | Definition |
|---|---|
| Parallelogram | Both pairs of opposite sides are parallel |
| Rhombus | Parallelogram with four congruent sides |
| Rectangle | Parallelogram with four right angles |
| Square | Parallelogram with four congruent sides and four right angles |
| Trapezoid | Quadrilateral with exactly one pair of parallel sides |
| Isosceles Trapezoid | Trapezoid with legs that are congruent |
| Kite | Quadrilateral with two pairs of consecutive sides congruent and no opposite sides congruent |
Now, let's find the slopes of the sides using the Slope Formula.
| Side | Slope Formula | Simplified |
|---|---|---|
| Slope of QU: ( 4,5), ( 12,14) | 14- 5/12- 4 | 9/8 |
| Slope of UA: ( 12,14), ( 20, 5) | 5- 14/20- 12 | - 9/8 |
| Slope of AD: ( 20, 5), ( 12, -4) | -4- 5/12- 20 | 9/8 |
| Slope of DQ: ( 12, -4), ( 4,5) | 5-( -4)/4- 12 | - 9/8 |
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 a parallelogram. Let's multiply the slopes of two consecutive sides 9/8 ( - 9/8 ) = - 81/64 Since the product is - 8164≠ - 1 the sides are not opposite reciprocals. Therefore, the 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 QU: ( 4,5), ( 12,14) | sqrt(( 12- 4)^2+( 14- 5)^2) | sqrt(145) |
| Length of UA: ( 12,14), ( 20, 5) | sqrt(( 20- 12)^2+( 5- 14)^2) | sqrt(145) |
| Length of AD: ( 20, 5), ( 12, -4) | sqrt(( 12- 20)^2+( -4- 5)^2) | sqrt(145) |
| Length of DQ: ( 12, -4), ( 4,5) | sqrt(( 4- 12)^2+( 5-( -4))^2) | sqrt(145) |
Our parallelogram has four congruent sides. Therefore, the most precise name for this quadrilateral is a rhombus.