Evaluating a graph of a proportional relationship Friday

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Evaluating a graph of a proportional relationship Friday, September 12

Evaluating a graph of a proportional relationship Friday, September 12

Learning Target I will be able to: • explain the unit rate (constant of

Learning Target I will be able to: • explain the unit rate (constant of proportionality) on graphs and equations; • identify unit rates on a proportional graph and explain points such as (0, 0) and (1, r); and • represent the proportional relationship as an equation in the form y=kx.

Evaluating the graph What is the title on the graph? What is a commission?

Evaluating the graph What is the title on the graph? What is a commission? An amount of money paid to someone for selling something. Typical jobs where commissions are earned: • Sales jobs—who can give an example? • Real Estate – earn commissions on the sale of a home • Professional sports agents: http: //www. forbes. com/sites/jasonbelzer/2013/07/31/the-worlds-mostpowerful-sports-agents/

Evaluating the graph What is represented on the x-axis on this graph? What is

Evaluating the graph What is represented on the x-axis on this graph? What is represented on the yaxis on this graph? What does the point (80, 6) on the graph mean? The coordinate pair on the graph are represented as (x, y) In this case what is x? What does the 80 mean? The 80 represents the amount of the purchase. What is the y value that is given on this graph? What does the 6 mean? The 6 represents the commission earned on $80 of purchases. If purchases were $160, how much would the commission be? If purchases were $40, how much would commission be?

Characteristics of a proportional graph These graphs must go through the origin (0, 0).

Characteristics of a proportional graph These graphs must go through the origin (0, 0). The point on the graph where x = 1 indicates the unit rate (1, r) Proportional graphs have straight lines

Finding the unit rate The point on the graph where x = 1 indicates

Finding the unit rate The point on the graph where x = 1 indicates the unit rate (1, r) What is the unit rate: It is the value of y when x=1.

Can you write the equation for this graph?

Can you write the equation for this graph?

Identifying characteristics of a proportional graph What does the point (0, 0) mean on

Identifying characteristics of a proportional graph What does the point (0, 0) mean on this graph? It means that when you first start (zero time) the sloth has not gone any distance. What does the point (1, r) represent on the graph? (1, r) = (1, 6) r = unit rate or 6 feet/minute Is the point (1, r) the same as (1, x)? Yes they are the same value, but in proportional graphs, r means that it is the unit rate. (0, 0)

Can you write the equation for this graph?

Can you write the equation for this graph?

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds What

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds What does the point (0, 0) mean on this graph? It means that for zero dollars you would get 0 pounds What is represented on the x-axis? US Dollars What is represented on the y-axis? British pounds What does this point represent? It means that for $3 you could exchange it for 2 British pounds.

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds How

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds How can we find the unit rate (1, r) on this graph? We could start with the rate of 2/3 and change it to a unit rate.

Can you write the equation for this graph?

Can you write the equation for this graph?

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds What

Identifying characteristics of a proportional graph Exchange rate US dollars to British pounds What does the point (0, 0) mean on this graph? It means that for zero web visits you would have 0 downloads. What is represented on the x-axis? Number of web visits. What is represented on the y-axis? Number of downloads. What does this point represent? It means that for 24 web visits you would have 8 downloads

Identifying characteristics of a proportional graph How can we find the unit rate (1,

Identifying characteristics of a proportional graph How can we find the unit rate (1, r) on this graph? We could start with the rate of 4/12 and change it to a unit rate.

Can you write the equation for this graph?

Can you write the equation for this graph?

Rate your learning I will be able to: • explain the unit rate (constant

Rate your learning I will be able to: • explain the unit rate (constant of proportionality) on graphs and equations; • identify unit rates on a proportional graph and explain points such as (0, 0) and (1, r); and • represent the proportional relationship as an equation in the form y=kx.