Complete the equation of the line through (2, 1) and (5, -8).
use exact numbers.
y =

y = -3x + 7

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Algebra I

Equality Properties

Slope Formula:

Slope-Intercept Form: y = mx + b

m - slope b - y-intercept

Step-by-step explanation:

Step 1: Define

Point (2, 1)

Point (5, -8)

Step 2: Find slope m

Simply plug in the 2 coordinates into the slope formula to find slope m

Substitute [SF]:                    Subtract:                              Divide:                                

Step 3: Find y-intercept b

Substitute in m [SIF]:                    y = -3x + bSubstitute in point:                       1 = -3(2) + bMultiply:                                        1 = -6 + bIsolate b:                                       7 = b

Step 4: Write Equation

Substitute in b [SIF]:                    y = -3x + 7