Answer:
The slope of AB is - 2,
Slope of BC is \frac{1}{2}
2
1
Slope of CD is -\frac{3}{4}−
4
3
Slope of AD is \frac{1}{2}
2
1
,
ABCD is trapezoid because one pair of opposite sides is parallel.
Step-by-step explanation:
Given vertices of quadrilateral ABCD,
A(−1, −1) , B(−3, 3) , C(1, 5) , and D(5, 2),
∵ Slope of a line passes through two points (x_1, y_1)(x
1
,y
1
) and (x_2, y_2)(x
2
,y
2
) is,
m=\frac{y_2-y_1}{xc_2-x_1}m=
xc
2
−x
1
y
2
−y
1
Thus, the slope of AB = \frac{3+1}{-3+1}=\frac{4}{-2}=-2
−3+1
3+1
=
−2
4
=−2
Slope of BC = \frac{5-3}{1+3}=\frac{2}{4}=\frac{1}{2}
1+3
5−3
=
4
2
=
2
1
Slope of CD = \frac{2-5}{5-1}=-\frac{3}{4}
5−1
2−5
=−
4
3
Slope of DA = \frac{-1-2}{-1-5}=\frac{-3}{-6}=\frac{1}{2}
−1−5
−1−2
=
−6
−3
=
2
1
Since, when two line segment having the same slope then they are parallel to each other.
∴ BC ║ DA
A quadrilateral only having two parallel sides is called trapezoid,
Hence, ABCD is a trapezoid.
