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Recall the classification of quadrilaterals. You can begin by finding the slopes of the sides.
Square
We will 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 |
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, we will find the slopes of the sides using the Slope Formula.
Side | Slope Formula | Simplified |
---|---|---|
Slope of QM: ( - 12,- 11), ( - 14,4) | 4-( - 11)/- 14-( - 12) | - 15/2 |
Slope of MN: ( - 14,4), ( 1, 6) | 6- 4/1-( - 14) | 2/15 |
Slope of NP: ( 1, 6), ( 3, - 9) | - 9- 6/3- 1 | - 15/2 |
Slope of PQ: ( 3, - 9), ( - 12,- 11) | - 11-( - 9)/- 12- 3 | 2/15 |
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. Additionally, the consecutive sides are perpendicular, as their slopes are opposite reciprocals. - 15/2 ( 2/15 ) = - 1 Therefore, our parallelogram is either a rectangle or a square. To check, we can find the lengths of its sides using the Distance Formula.
Side | Distance Formula | Simplified |
---|---|---|
Length of QM: ( - 12,- 11), ( - 14,4) | sqrt(( - 14-( - 12))^2+( 4-( - 11))^2) | sqrt(229) |
Length of MN: ( - 14,4), ( 1, 6) | sqrt(( 1-( - 14))^2+( 6- 4)^2) | sqrt(229) |
Length of NP: ( 1, 6), ( 3, - 9) | sqrt(( 3- 1)^2+( - 9- 6)^2) | sqrt(229) |
Length of PQ: ( 3, - 9), ( - 12,- 11) | sqrt(( - 12- 3)^2+( - 11-( - 9))^2) | sqrt(229) |
Our parallelogram has four congruent sides. Therefore, the most precise name for this quadrilateral is square.