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Find x for a predicted y on a line of best fit

Year 8 maths · Fieldbook Learning

Name ______________________ Date __________

Set the equation equal to the given y and solve for x.

  1. A line of best fit for age of a car (x) and its price (y) is y = 7x + 40. For what value of x does the line predict y = 89?
  2. A line of best fit for shoe size (x) and height (y) is y = 5x + 36. For what value of x does the line predict y = 91?
  3. A line of best fit for temperature (x) and ice creams sold (y) is y = 7x + 28. For what value of x does the line predict y = 42?
  4. A line of best fit for temperature (x) and ice creams sold (y) is y = 3x + 35. For what value of x does the line predict y = 59?
  5. A line of best fit for temperature (x) and ice creams sold (y) is y = 2x + 40. For what value of x does the line predict y = 46?
  6. A line of best fit for temperature (x) and ice creams sold (y) is y = 5x + 12. For what value of x does the line predict y = 47?
  7. A line of best fit for shoe size (x) and height (y) is y = 11x + 11. For what value of x does the line predict y = 88?
  8. A line of best fit for shoe size (x) and height (y) is y = 10x + 32. For what value of x does the line predict y = 152?
  9. A line of best fit for hours studied (x) and test score (y) is y = 4x + 34. For what value of x does the line predict y = 106?
  10. A line of best fit for temperature (x) and ice creams sold (y) is y = 14x + 24. For what value of x does the line predict y = 206?
  11. A line of best fit for temperature (x) and ice creams sold (y) is y = 6x + 19. For what value of x does the line predict y = 103?
  12. A line of best fit for temperature (x) and ice creams sold (y) is y = 6x + 28. For what value of x does the line predict y = 46?
  13. A line of best fit for shoe size (x) and height (y) is y = 19x + 9. For what value of x does the line predict y = 446?
  14. A line of best fit for temperature (x) and ice creams sold (y) is y = 7x + 20. For what value of x does the line predict y = 195?
  15. A line of best fit for shoe size (x) and height (y) is y = 9x + 38. For what value of x does the line predict y = 137?
  16. A line of best fit for hours studied (x) and test score (y) is y = 20x + 35. For what value of x does the line predict y = 155?
  17. A line of best fit for shoe size (x) and height (y) is y = 6x + 12. For what value of x does the line predict y = 108?
  18. A line of best fit for hours studied (x) and test score (y) is y = 16x + 15. For what value of x does the line predict y = 303?
  19. A line of best fit for hours of sleep (x) and minutes to fall asleep (y) is y = 4x + 8. For what value of x does the line predict y = 96?
  20. A line of best fit for temperature (x) and ice creams sold (y) is y = 21x + 15. For what value of x does the line predict y = 624?
More free practice: fieldbooklearning.com/au/practice/year-8/find-x-for-a-predicted-y-on-a-line-of-best-fit/

Play it as a quiz game

6 of these questions as multiple choice, with near-miss wrong answers, ready for Kahoot or Blooket.

  1. Download the game's own question template: in Kahoot, Add question → Import spreadsheet; in Blooket, Create a set → Spreadsheet import.
  2. Click the matching button below, then click the first empty question row of the template and paste.
  3. Save the template (Kahoot needs .xlsx, Blooket .csv) and upload it.
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Answer key: Find x for a predicted y on a line of best fit

  1. 7
  2. 11
  3. 2
  4. 8
  5. 3
  6. 7
  7. 7
  8. 12
  9. 18
  10. 13
  11. 14
  12. 3
  13. 23
  14. 25
  15. 11
  16. 6
  17. 16
  18. 18
  19. 22
  20. 29