Wed, 12/3 SWBAT…compute slope Agenda 1. WU (5 min) 2. Notes on slope (35 min) Warm-Up: 1. Set up your notes. Topic is “Slope” HW #3: Slopes of lines (front & back)

How do engineers build bridges?

How do engineers build roads?

How do builders build roofs?

How can we write 7% as a fraction?

7% as a fraction?? Remember than any percent is a part of 100.

The grade or incline of a road is the same as slope Here is the picture: 7 feet 100 feet

Slope of a line (m) To find the slope, use the formula 4 4 (elevacion) (desplazamiento)

Slope of a line (m) To find the slope, use the formula 4 4

Slope of a line (m) Find the slope of the following lines: 1 2 A) B) 2 3

Why do we use m for slope? Possibly because m comes from the French word “monter”, which means to climb

Slope of a line (m) Is the slope positive or negative? Answer: Positive, read from left to right

Slope of a line (m) The last 2 lines had a positive slope, let’s look at slopes with negative slopes

Slope of a line (m) We still use rise over run, except the “stairs” are underneath the line. 3 -2

Your turn

“Official” Definition of Slope Slope is the change in the vertical distance (rise) over the change in the horizontal distance (run) Pendiente: Razon del cambio en la coordenada y (elevacion) al cambio correspondiente en la coordenada x (desplazamiento) a medida que uno se mueve de un punto a otra en una recta.

Find the slope of the line that passes through (1, 0) and (-1, -1). Question (x 1, y 1 ) (x 2, y 2 ) (To see the slope visually… Plot these points. Connect the line (don’t forget arrows)).

1 2 m  What the graph looks like

Find the rate of change: xy

Directions: Find the value of r so the line that passes through each pair of points has the given slope. (12, 10), (-2, r) m = -4

Horizontal lines have a slope of ___ Vertical lines have a slope of ___ HorizontalVertical m = 0 m = undefined

Practice Problem A horizontal lines passes through (2, 5). What other point does the line contain? 1. (2,3) 2. (0,5) 3. (5,10) 4. (0,2)