4 1 Using Graphs to Relate Two Quantities

4. 1 Using Graphs to Relate Two Quantities: Analyze: to examine something in great detail in order to understand it better. Interpret: To establish or explain the meaning or significance of something. Describe: To give an account of something by giving details of its characteristics

Graphs:

In math we use graphs to represent real world situations. A well rounded Algebra 1 student must be able to work with graphs and be able to: 1. Analyze graphs, 2. Match graphs to given situations, and 3. Sketch graphs

Analyzing Graphs: Given any graph, we must be able to describe the information it is providing by using the labeling (variables) of each graph. Ex:

Looking at the labels of the graph(variables), we can see that this graph has to do with volume of a balloon (vertical label: y-axis) over time (horizontal label: x-axis). This means, that as time goes by, the volume in the balloon increases.

YOU TRY IT: b) Describe how the variables are related. Temperatures of H 20 Temp (Fo) a) What are the variables in the graph? Depth

YOU TRY IT: (Solution) b) The temperature of the water decreases as depth increases. Temp (Fo) a) The variables are depth (Independent) and temperature (dependent) Temperatures of H 20 Depth

Matching graphs: Data from a table is often displayed using a graph to visually represent the relationship between the variables. It is our job to math the corresponding table with the graph. Ex:

Ex: Matching graphs: looking at the table, from point to point, we see that it increases rapidly from one to the other (not constant) which means it is not going to create a line. The answer is B.

YOU TRY IT: Match the graph to the proper situation.

YOU TRY IT: (SOLUTION) Match the graph to the proper situation. 4) C: The first point is (1, 50) 5) B: The first point is (1, 80) 6) A: The first point is (1, 60)

Sketching Graphs: Data from a given situation can be transferred to a graph. We must once again keep in mind the Independent variable (x) and the independent variable (y). JESSIE WAS HERE Ex:

Sketching Graphs (SOLUTION):

YOU TRY IT: Sketch the graph to represent the following situation. 1) Suppose you want to buy several cans of soup that cost $2. 00 each. How is the cost related to the number of cans you buy.

YOU TRY IT: (SOLUTION) Cost $ We know that each can costs $2. 00 Cans (x) Dollars (y) 1 2 2 4 3 6 4 8 Cans The cost will vary DIRECTLY with # of cans.

VIDEOS: Graphs https: //www. khanacademy. org/math/arithmetic/ applying-math-reasoningtopic/reading_data/v/u 08 -l 1 -t 2 -we 2 -reading-linegraphs https: //www. khanacademy. org/math/arithmetic/ applying-math-reasoningtopic/reading_data/v/reading-bar-charts-1

CLASSWORK: Page 237 -239 Problems: As many as needed to master the concept