1. 1.3 Notes: Linear Equations in 2 Variables
Date:
1.3 Notes: Linear Equations in 2 Variables
Lesson Objective: Write and graph linear equa-tions in 2 variables and use slope to identify | | and _|_ lines and solve real-life problems.
You will need: pencil
Real-World App: What is Starbuck’s sales per share?
This is Jeopardy!!!: This is how the point-slope formula is derived.

2. Lesson 1: Writing Linear Equations in 2 Variables
Slope = m = ___________

3. Lesson 1: Writing Linear Equations in 2 Variables
Slope = m = ___________
Point-Slope Form:

4. Lesson 1: Writing Linear Equations in 2 Variables
Slope = m = ___________
Point-Slope Form:
Slope-Intercept Form:

5. Lesson 1: Writing Linear Equations in 2 Variables
Slope = m = ___________
Point-Slope Form:
Slope-Intercept Form:
Find the point-slope and the slope-intercept form of the equation of the line that has a slope of 2 and passes through the point (3, -7). Find 3 additional points on the line.

6. Lesson 2: Finding | | and _|_ Lines
Find the slope-intercept form of the equations of the lines that pass through the point (-4, 1) and are | | to and _|_ to the line 5x – 3y = 8.
| |:
_|_:

7. Lesson 3: Using Slope as a Ratio

8. Lesson 4: Using Slope as a Rate of Change
A sales representative receives $500 in salary plus $25 for every item sold. Find the linear equation and graph the situation. Determine the slope and y-intercept and interpret the slope and y-intercept in the
context of the situation.

9. Lesson 5: Straight-Line Depreciation
A person purchases a car for $25,920. After 11 years, the car will have to be replaced. Its value at that time is expected to be $ Write a linear equation giving the value, V, of the car during the 11 years in which it will be used.

10. Lesson 6: Predicting Sales per Share
The sales per share for Starbucks Corp. were $6.97 in 2001 and $8.47 in Using only this information, write a linear equation that gives the sales per share in terms of the year. Then predict the sales per share for 2016.

11. 1.3: DIGI Yes or No
Find the slope-intercept forms of the equa-tions of the lines that pass through the point (2, -1) and are | | to and _|_ to the line 2x – 3y = 5.
The maximum recommended slope of a wheelchair ramp is A business is instal-ling a ramp that rises 22” over a horizontal length of 24’. Is the ramp steeper than recommended?
Continued on next slide

12. 1.3: DIGI Continued
A kitchen appliance manufacturing compa-ny determines that the total cost in dollars of producing x units of a blender is C = 25x Describe the practical significance of the y-intercept and slope of this line.
A college purchased exercise equipment worth $12,000. The equipment has a useful life of 8 years. The salvage value at the end of 8 years is $ Write a linear equation that describes the book value of the equipment.