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Use the table to determine whether the relationship is proportional. If so, write an equation for the relationship. Tell what each variable you used represents.

Use the table to determine whether the relationship is proportional. If so, write-example-1

1 Answer

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Answer:

y = 25x, proportional relationship

Explanation:

Let "x" = number of hours read (replace with "h" if that's the variable your teacher wants)

Let "y" = number of pages read (you can use any other variables if you want)

Let's first calculate the slope using
(y_(1) - y_(2))/(x_(1) - x_(2)) with any two points, I'm going to use (2, 50) and (3, 75):


(y_(1) - y_(2))/(x_(1) - x_(2)) = (50 - 75)/(2 - 3) = (-25)/(-1) = 25

Our slope is m = 25.

Now we can use the point-slope form
y-y_(1) = m(x-x_(1)) with our slope and any point (I'll use (2, 50)) to figure out the equation:


y-y_(1) = m(x-x_(1)) \\ y-50 = 25(x-2)

Simplify:


y-50 = 25(x-2)\\y-50 = 25 x -50\\ y = 25x

Since the slope is positive, the relationship is proportional.

User Ruthie
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