Question

What is the perimeter of the triangle.

Answer 1

P = 36 units

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Equality Properties

Algebra I

• Reading a Cartesian Plane

Geometry

• Perimeter is all the side lengths added together

Trigonometry

• [Right Triangles Only] Pythagorean Theorem: a² + b² = c²

Explanation:

Step 1: Define

We can determine some of the perimeter already by finding the lengths of the legs.

Bottom Leg = 12 units

Vertical Leg = 9 units

Step 2: Determine 3rd Leg

1. Substitute [PT]: 12² + 9² = c²
2. Exponents: 144 + 81 = c²
3. Add: 225 = c²
4. Isolate c: 15 = c
5. Rewrite: c = 15

Step 3: Determine Perimeter

1. Substitute: P = 12 units + 9 units + 15 units
2. Add: P = 36 units