Question

What is the slope of the line that passes through the points (9, 5) and (21, 1)?

Write your answer in simplest form.

Answer 1

`\displaystyle m = (-1)/(3)`

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

• Coordinates (x, y)
• Slope Formula:
  `\displaystyle m = (y_2-y_1)/(x_2-x_1)`

Explanation:

Step 1: Define

Point (9, 5)

Point (21, 1)

Step 2: Solve for slope m

1. Substitute in points [Slope Formula]:
   `\displaystyle m = (1-5)/(21-9)`
2. [Fraction] Subtract:
   `\displaystyle m = (-4)/(12)`
3. [Fraction] Simplify:
   `\displaystyle m = (-1)/(3)`