Uculating the Perimeter of a Triangle GO
y
Triangle ABC is an isosceles triangle in which side
AB = AC. What is the perimeter of triangle ABC?
5
4
O 5+ 10 units
3
2
O 10 + 10 units
1
2
10/10 units
2.
3
- 5 4 -3 -2 -1
-1
4
5
O 50 units
B
-2
А
c
-5

10 + √10  

Explanation:

Assume your triangle is like the one below.

The coordinates of the vertices are

A = (-2,-4), B = (-2,-1) A = (-2,-4)

1. Calculate AC

AC = 3 - (-2) = 3 + 2 = 5

2. Calculate AB

AB = AC = 5

3. Calculate BC

We can use the Pythagorean theorem:

BC² = BD² + CD² = 3² + 1² = 9 + 1 = 10

BC = √10

4. Calculate the perimeter

p = AB + AC + BC = 5 + 5 + √10 = 10 + √10

b a mature ovary of a plant.