Extra practice with SLOPE and RATE OF CHANGE

Extra practice with SLOPE and RATE OF CHANGE!

RATE OF CHANGE Things to Remember: Rate of change = Change in Dependent Variable Change in Independent Variable How is this related to Slope? SLOPE = Change in Y values Change in X values

Let’s find Rate of Change or Slope from a TABLE! Cost of Renting a Computer Number of Days Rental Charge 1 2 3 4 5 $60 $75 $90 $105 $120 This is the same table without the realworld data. How is it similar to our tables used to calculate SLOPE? X Y 1 60 2 75 3 90 4 105 5 120

Let’s find Rate of Change (Slope) from a TABLE! Cost of Renting a Computer Number of Days Rental Charge 1 2 3 4 5 $60 $75 $90 $105 $120 1. Choose two points, any two points. 2. Write the chosen points as coordinate pairs. 3. Identify the x 1, x 2, y 1, y 2. 4. Substitute the values into the slope formula. 5. Perform the subtractions. 6. Reduce if necessary.

Let’s find Rate of Change (Slope) from a TABLE! Cost of Renting a Computer Number of Days Rental Charge 1 2 3 4 5 $60 $75 $90 $105 $120 1. Choose two points, any two points. 2. Write the chosen points as coordinate pairs. (2, 75) (4, 105)

Cost of Renting a Computer Number of Days Rental Charge 1 $60 2 $75 3 $90 4 $105 5 $120 Let’s find Rate of Change (Slope) from a TABLE! 3. Identify the x 1, x 2, y 1, y 2. X 1 Y 1 (2, 75) X 2 Y 2 (4, 105) y 2 – y 1 m = x – x = 105 – 75 2 1 4. Substitute the values into the slope formula. 5. Perform the subtractions. 6. Reduce if necessary. 4 -2 = 30 = 15 2

Time (hours) Temperature (F) 1 -2 4 7 7 16 10 25 13 34 1. Choose two points, any two points. 2. Write the chosen points as coordinate pairs. 3. Identify the x 1, x 2, y 1, y 2. 4. Substitute the values into the slope formula. 5. Perform the subtractions. 6. Reduce if necessary.

Time (hours) Temperature (F) 1 -2 4 7 7 16 10 25 13 34 (4, 7) (7, 16) ( x 1 , y 1 ) ( x 2, y 2) m = 16 – 7 = 9 = 7 -4 3 3

Brain Break!!

Let’s find Rate of Change or Slope from a GRAPH! 1. Choose two points, two points that lay on a grid line. 2. Write the chosen points as coordinate pairs. 3. Identify the x 1, x 2, y 1, y 2. 4. Substitute the values into the slope formula. 5. Perform the subtractions. 6. Reduce if necessary. NOTICE: The steps are the SAME!

Let’s find Rate of Change or Slope from a GRAPH! (-3, -1) (2, 3) ( x 1 , y 1 ) ( x 2, y 2) m = 3 – -1 = 2 – -3 4 5

You have lots of choices!! Only choose two. (-2, 0) (0, -2) ( x 1 , y 1 ) ( x 2, y 2) Do you remember the name of these points? m = -2 – 0 = -2 0 – -2 2 = -1

Independent Practice!! • Complete exercises on workbook. • Show ALL work! • Remember it is independent – don’t look at your neighbor’s work!