Question

Find the value of a that makes the ordered pair a solution of the equation.

9x - 5y = -9;(a-1,9)

Answer 1

a = 5

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

Algebra I

Equality Properties

• Multiplication Property of Equality
• Division Property of Equality
• Addition Property of Equality
• Subtraction Property of Equality

Terms/Coefficients

Coordinate Planes

• Coordinates (x, y)
• Equations

Explanation:

Step 1: Define

Identify.

9x - 5y = -9

(a - 1, 9)

Step 2: Solve for a

1. Substitute in coordinate [Equation]: 9(a - 1) - 5(9) = -9
2. Evaluate [Order of Operations]: 9(a - 1) - 45 = -9
3. [Addition Property of Equality] Add 45 on both sides: 9(a - 1) = 36
4. [Division Property of Equality] Divide 9 on both sides: a - 1 = 4
5. [Addition Property of Equality] Add 1 on both sides: a = 5