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Writing an equation and drawing its graph to model a real-world situat – Tutorial

Writing an equation and drawing its graph to model a real-world situation: Basic




In this lesson, we solve real world problems which are modeled by an equation. The equation describing the problem is written and its graph is plotted.

Jenny has savings of $42 and earns $7 for each hour of lawn mowing. If y is the total amount with Jenny and x is the number of hours he works, write and equation in y and x and graph it.

Solution


Step 1:

The equation representing the problem in x and y is

y = 42 + 7x

Step 2:

The plot is

Writing an equation and drawing its graph to model a real-world situation: Basic Example1 Step2

Phil’s party costs $110 plus $7 for every guest he invites. Let y be the total cost of party and x be the number of guests. Write an equation in x and y and graph it.

Solution


Step 1:

The equation representing the problem in x and y is y =110 + 7x

Step 2:

The plot is

Writing an equation and drawing its graph to model a real-world situation: Basic Example2 Step2