SLOPE and RATE of CHANGE

Slope – a specific rate of change. It measures the change in the vertical axis over the change in the horizontal axis. - a ratio that describes steepness.

Positive vs. Negative A line with a positive slope goes upward from left to right A line with a negative slope goes downward from left to right

Count using the coordinate grid Calculating slope from a graph Use coordinates themselves

A (0, 12) and B (100, 212) Calculating slope from 2 given points (4,0) and (-1, 5)

The slope of a horizontal line is zero. Division by zero is undefined. The slope of a vertical line is undefined. Horizontal vs. Vertical Lines Some lines are neither upward or downward sloping. They can be calculated the same way.

A summary is also in the Book on page 312

Choose 2 points and find the slope Calculating slope from a table of values If the change between consecutive pairs of data are constant, the relationship is linear. X Y X Y Try the calculation again using two different points.

Slope is also sometimes referred to as rate of change. Independent Variable = x Dependent Variable = y Rate of Change - a comparison between two quantities that are changing. - Allows you to see the relationship between 2 quantities that are changing.

If you type 140 words in four minutes, what is your rate? Calculating Rate of Change If you buy 5 yards of fabric for $19.95, what is the rate? You travel miles on 12 gallons of gas, what is your rate?

¿Preguntas? est-ce que vous en avez?

Assignments Class Work Page 312#1 – 6 Page 313#7 – 9, 11 – 21 odd, 22 – 26 #27 – 35 odd, 36 – 41 Page 314#43, 48 – 60, 62 Early Finishers#66 – 71 Homework Page 315 #