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Steven earns extra money babysitting he charges $33 for 4 hours and $57.75 for 7 hours entering an equation to represent the relationship let x represent the number of hours Stephen babysits and let y represent the amount he charges the equation is y = ​

User XTrimy
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1 Answer

6 votes

Answer:

y = 8.25x

Explanation:

Linear Modeling

Some events can be modeled as linear functions. If a situation comes where a linear model is suitable, then we need two sample points to make the model and predict unknown behaviors.

The linear function can be expressed in the slope-intercept format:


y=mx+b

The equation of a line passing through points (x1,y1) and (x2,y2) can be found as follows:


\displaystyle y-y_1=(y_2-y_1)/(x_2-x_1)(x-x_1)

Let's use linear modeling to represent Steven's earnings he makes babysitting. Call y the money he charges by x hours of work.

We know he charges y1=$33 for x1=4 hours, and y2=$57.75 for x2=7 hours. The ordered pairs are (4,33) and ( 7, 57.75)

Computing the equation of the line we have:


\displaystyle y-33=(57.75-33)/(7-4)(x-4)

Operating:


\displaystyle y-33=(24.75)/(3)(x-4)


y - 33 = 8.25( x - 4 )


y = 8.25x - 33 + 33

y = 8.25x

There is a proportional relationship.

User Milo Christiansen
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