Surprise!
For a new activity, Lisa purchases a camera for $525. Lisa pays $8.99 for each roll she gets developed. Calculate how much Lisa’s new activity is costing her based on the number of film rolls she needs to develop.
What is the equation for this situation? the y=mx + b?
y=525 + 8.99x
or y=8.99x + 525
Roy earns an hourly wage and occasionally receives a bonus that is paid on the first day of the month. This month, Roy’s total pay was $800.50 after working 72 hours and $1,200.00 after working 104 hours.
What are the two points (x,y) for this information? (don't forget that x is usually time and y is whatever the other part is :)
(72,800.00) and (104, 1200.00)
What makes a function proportional or
non-proportional?
Proportional if it goes through the origin
Non-Proportional if it does NOT go through the origin
For a new activity, Lisa purchases a camera for $525. Lisa pays $8.99 for each roll she gets developed. Calculate how much Lisa’s new activity is costing her based on the number of film rolls she needs to develop.
What is the dependent variable and what does it represent in the problem?
Y - how much it costs
Roy earns an hourly wage and occasionally receives a bonus that is paid on the first day of the month. This month, Roy’s total pay was $800.50 after working 72 hours and $1,200.00 after working 104 hours.
What is the slope for these points? (m)
m=12.5 or m= 400/32
(-19, -4) (-10,1)
What is the slope?
m=5/9
For a new activity, Lisa purchases a camera for $525. Lisa pays $8.99 for each roll she gets developed. Calculate how much Lisa’s new activity is costing her based on the number of film rolls she needs to develop.
What is the independent variable and what does it represent in the problem?
X - the number of films
Roy earns an hourly wage and occasionally receives a bonus that is paid on the first day of the month. This month, Roy’s total pay was $800.50 after working 72 hours and $1,200.00 after working 104 hours.
What is your b for this equation y=12.5x + b? (hint: Use a point if you don't know what to do!!!)
b=-100
How do you find the equation of a line if you only have the slope and need to find the b?
Plug in a point - any point!