Slope in our Slope in our SocietySocietyInvestigations of SlopeInvestigations of SlopeElizabeth Thompson, PhDElizabeth Thompson, PhD

ALEX / GEMS Project ContributionALEX / GEMS Project Contribution

Have you ever seen a Have you ever seen a sign like this on the sign like this on the

highway?highway?

What do you think it is for?What do you think it is for?

Why would a driver need Why would a driver need to see this sign?to see this sign?

Here is a picture of a run-Here is a picture of a run-away truck ramp.away truck ramp.

Have you seen one before? Where?Have you seen one before? Where?

Usually, a road sign Usually, a road sign expresses the grade (slope) expresses the grade (slope)

of a road as a percentof a road as a percent

If you had a ramp like this, If you had a ramp like this, how would you express it’s how would you express it’s

SLOPE as a percent?SLOPE as a percent?

RISE = 3

RUN = 12

Wheelchair RampsWheelchair Ramps

Ramp steepness is governed Ramp steepness is governed by the American’s with by the American’s with Disabilities ACT.Disabilities ACT.

ADA Accessibility Guidelines ADA Accessibility Guidelines for Buildings and Facilities for Buildings and Facilities (ADAAG) are located at: (ADAAG) are located at: http://www.access-board.gov/http://www.access-board.gov/adaag/html/adaag.htm#4.8adaag/html/adaag.htm#4.8

How steep of a ramp should be acceptable for a person in a wheelchair?

Stairs are an excellent Stairs are an excellent example of slope example of slope

run

rise

Most of us are familiar with associating ‘stairs’

with ‘slope’.

Do you have any questions about finding

the slope of stairs?

You can place a board over any set of stairs and get a ramp, but would the slope always be acceptable for

strollers and wheelchairs?

Using the Slope Formula Using the Slope Formula when given 2 endpointswhen given 2 endpoints

1

2

2

2

x

ym

13

22

y

m

This is an XLets make it our 1st X

21

2

2

4

13

22

m12

12

x

yym

12

12

xx

yym

This is a Y. Lets make it our 1st Y

Another X. It’s our 2nd one.

Another Y. Its our 2nd one. Lets plug it in and

solve for slope (m).

Use the following endpoints Use the following endpoints to calculate slope with the to calculate slope with the given formula. Could these given formula. Could these lines be wheelchair ramps?lines be wheelchair ramps?

Practice Problems:Practice Problems:

1.1. (4,6) (-2,3) (4,6) (-2,3)

2.2. (5,-7) (6,7)(5,-7) (6,7)

3.3. (3,-2) (4,3)(3,-2) (4,3)12

12

xx

yym

ASSIGNMENT: ASSIGNMENT:

Reporting on Safe Slopes Reporting on Safe Slopes in our Schoolin our School

See Handout:See Handout: Groups of 4-5Groups of 4-5