Slope & Y-InterceptIn Context

4 3 2 1 0

In addition to level 3.0 and above and beyond what was taught in class,  the student may:· Make connection with other concepts in math· Make connection with other content areas.

The student will be able to interpret linear models. - Interpret slope in context of data. - Write the line-of-best-fit for a scatter plot. - Distinguish between correlation and causation. - Use technology to calculate correlation coefficient.

The student will be able to: - Determine if a scatter plot has positive or negative correlation and if the correlation is weak or strong. - Use the correlation coefficient to interpret the strength of a correlation.

With help from theteacher, the student haspartial success interpreting linear models or scatter plots.

Even with help, the student has no success understanding the concept of a linear models.

Learning Goal #2 for Focus 4 (HS.S-ID.C.7, 8 & 9, HS.S-ID.B.6, HS.F-IF.B.6): The student will be able to interpret linear models.

Using Slope-Intercept Form

• In a real-life context the y-intercept often represents an initial amount and the slope often represents a rate of change.

• Knowing this structure can help you understand equations, write equations in slope-intercept form and understand graphs.

Buying A Computer

• You are buying a computer on layaway. You make a $250 deposit and then make weekly payments.• The equation A = 850 – 50T represents this

situation.

• What is the slope?• What does it mean in this situation?• What is the y-intercept?• What does it mean in this situation?• What is the original amount of the computer?

Image from http://pixabay.com/en/computer-hardware-keyboard-modern-156513/

-50

(0, 850)

$1,100 [850 + 250 deposit]

Access Ramps

• Wheelchair access ramps must be built according to very precise specifications so that the ramps are not too steep to maneuver a wheel chair. • If one is standing at the top of the ramp, y stands for

the height above the ground and x stands for the horizontal distance from the start of the ramp to the platform.

• The equation for the ramp is y = 1/12 x

y = 1/12x

• What is the meaning of the y-intercept in this particular situation?• Suppose you wish to build a wheelchair accessible

ramp into a building, and the first floor is 4 feet above the ground. Determine the how far out horizontally from the building should the ramp begin?

(0, 0)

(x, 4)

Wheelchair Access Ramp

•y = 1/12x•4 = 1/12x•48 = x•The ramp will need to be 48 feet long.

Image from http://wheelchairassistance.com/wheelchair-ramp/trifold-wheelchair-ramps.php