The perimeter of rectangle is 18 units
Solution:
The perimeter of rectangle is:
Perimeter = 2( length + width)
Rectangle ABCD has vertices at A (-1, 1), B (2, 1), C (2, -5), and D (-1, -5)
Let AB be the length
Let BC be the width
Find distance between A and B
The distance between two points is given as:
![d = √((y_2-y_1)^2+(x_2-x_1)^2)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/2ftincbwfki0diqd0wsk8nnpsv82m4pc8y.png)
![(x_1, y_1) = (-1, 1)\\\\(x_2, y_2) = (2, 1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/cucb3jvd7hz9yidd2vka1upp1pibxgjhca.png)
Therefore,
![d = √((1-1)^2+(2+1)^2)\\\\d = √(3^2)\\\\d = 3](https://img.qammunity.org/2021/formulas/mathematics/middle-school/4f2lp8qdqb2cbetngurbf6ra02vneauzt5.png)
Thus, AB = length = 3 units
Find the distance between B and C
![(x_1, y_1) = (2, 1)\\\\(x_2, y_2) = (2, -5)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/vips17zayo8folhbziaqk0o1od8hembcm4.png)
Therefore,
![d = √((5+1)^2+(2-2)^2)\\\\d = √(36)\\\\d = 6](https://img.qammunity.org/2021/formulas/mathematics/middle-school/81v4elf1blpv6347a0j6xx9uiq4fahhhcz.png)
Thus width = 6 units
Therefore,
Perimeter = 2(3+6) = 2(9) = 18
Thus perimeter of rectangle is 18 units