Answer:
a = 12
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality
Trigonometry
[Right Triangles Only] Pythagorean Theorem: a² + b² = c²
- a is a leg
- b is another leg
- c is the hypotenuse
Step-by-step explanation:
Step 1: Define
Identify variables
a = a
b = 9
c = 15
Step 2: Solve for a
- Substitute in variables [Pythagorean Theorem]: a² + 9² = 15²
- Evaluate exponents: a² + 81 = 225
- [Subtraction Property of Equality] Subtract 81 on both sides: a² = 144
- [Equality Property] Square root both sides: a = 12