Question

4.2 perimeter of quadrilaterals and triangles
find the perimeter of each triangle.
a.
6.1
57°
8.7
79°
44°
7.4
b.
9
4
5
12
c.
a
9 m
6 m
110°
4 m
b
c
a. units
b. units
c. meters

Explanation:

Step1: Recall perimeter formula

The perimeter $P$ of a triangle is $P=a + b + c$, where $a$, $b$, and $c$ are the side - lengths of the triangle.

Step2: Calculate perimeter of triangle a

For triangle a, with side - lengths $a = 6.1$, $b = 7.4$, and $c = 8.7$. Then $P=6.1 + 7.4+8.7=22.2$ units.

Step3: Calculate perimeter of triangle b

For triangle b, with side - lengths $a = 9$, $b = 5$, and $c = 12$. Then $P=9 + 5+12=26$ units.

Step4: Calculate perimeter of triangle c

For triangle c, with side - lengths $a = 6$, $b = 4$, and $c = 9$. Then $P=6 + 4+9=19$ meters.

Answer:

a. 22.2 units
b. 26 units
c. 19 meters