IXL | Write equations for proportional relationships from graphs

In his computer science class, Franco is learning how to program computer games. For his final project, Franco is creating his own multilevel game.

There is a proportional relationship between the number of levels Franco has created for his game,

and how long (in weeks) it took him to program them,

Write an equation for the relationship between x and

Simplify any fractions.

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In his computer science class, Franco is learning how to program computer games. For his final project, Franco is creating his own multilevel game.

There is a proportional relationship between the number of levels Franco has created for his game,

and how long (in weeks) it took him to program them,

Write an equation for the relationship between x and

Simplify any fractions.

The graph of a proportional relationship is a straight line passing through the origin

(

)

A proportional relationship between x and y can be modeled by the equation

The letter k is the constant ratio of y to

It is called the constant of proportionality.

To write an equation for the relationship between x and

first find the constant of proportionality. Start by identifying the coordinates of one of the points on the line.

Calculate the ratio of the

y-coordinate

to the

x-coordinate.

The constant of proportionality is 1 week per level.

Since the product 1x is commonly written without the 1, an equation for the relationship is:

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