Make a table of values, graph the ordered pairs, and then count how to move from one point to another.

By counting how to move from one point to another, similar to Part I.

*Think: the first answer says go up 1, then left 2 whereas the second says go down 1 then right 2. Both will wind up on the same line when graphed.

*It does not matter which way you subtract your y or x values as long as you subtract the two y’s and then the two x’s in the same order at order and NOT  .

m=slope and b=the y intercept

Plot the y intercept first

Use the slope (m) to plot two more points

Example: plot +2 first, then do up 2 over 3

Writing Equations in Slope Intercept Form

Part I: If given slope and one ordered pair slope = 2; (3, 11)

Substitute the slope and ordered pair into the equation y = mx + b

**Remember m = slope

Solve for b which is the y-intercept

Rewrite in slope intercept form by using the slope and y intercept

Example: slope = 2; (3, 11)

y = mx + b

11 = 2(3) + b Substitute the ordered pair into x and y

5 = b Solve for b ????

y = 2x + 5 Rewrite in slope intercept form

Part II: If given two ordered pairs (1, -5); (4, 7)

Find slope Part III on previous notes…..then basically follow the steps above

Substitute one of the ordered pairs and the slope into the equation y = mx + b

Solve for b which is the y-intercept

Rewrite in slope intercept form by using the slope and y intercept

Example: (1, -5); (4, 7)

Find slope

y = mx + b

Substitute 7 = 4(4) + b it does not matter which ordered pair you use

Solve -9 = b

Rewrite y = 4x - 9

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