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Sonny has entered a reading contest at the local library. After reading two books, he has read 396000 words of text. After five books, he has read 990000 words of text. Write a linear function in slope-intercept form to model his progress where

x is the number of books read and y is the total number of words read.

y= __________________



How many books will he need to read to reach a total of 10,000,000 words?

___________________

User TimVdG
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1 Answer

10 votes

Answer:

Please check the expalantion.

Explanation:

Let

  • x is the number of books read
  • y is the total number of words read

Given that:

After reading two books, he has read 396000 words of text.

  • Thus, we get the point (2, 396000).

After five books, he has read 990000 words of text.

  • Thus, we get the point (5, 990000).

As the function is linear, so we take the points

  • (2, 396000)
  • (5, 990000)

Determining the slope between (2, 396000) and (5, 990000)

(x₁, y₁) = (2, 396000)

(x₂, y₂) = (5, 990000)

Using the formula

Slope = m = [y₂ - y₁] / [x₂ - x₁]

= [990000 - 396000] / [5 - 2]

= 594000 / 3

= 198000

Thus, the slope of the line = m = 198000

substituting the point (2, 396000) and m = 198000 in the slope-intercept form of the linear equation to determine the y-intercept

y = mx+b

396000 = 198000(2) + b

flipe the equation

198000(2) + b = 396000

396000 + b = 396000

subtracting 396000 from both sides

396000 + b - 396000 = 396000 - 396000

b = 0

now substituting b = 0 and m = 198000 in the slope-intercept form of the linear equation to determine the y-intercept

y = mx+b

y = 198000x + 0

y = 198000x

Therefore, a linear function in slope-intercept form to model his progress is:

y = 198000x

Part b)

How many books will he need to read to reach a total of 10,000,000 words?

As we have already determined a linear function in slope-intercept form to model his progress.

y = 198000x

substituting y = 10,000,000 in the equation

y = 198000x

10,000,000 = 198000x

flip the equation

198000x = 10,000,000

dividing the both equation by 198000

198000x/198000 = 10,000,000/198000

x = 50.5

Thus, Sonny will need to read 50.5 books to read to reach a total of 10,000,000 words.

User Politinsa
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