Worksheets · Algebra 1

Excluded values worksheet

One question every time: what would make the bottom zero. Factor the denominator, set each factor to zero, and those are the values the expression cannot take.

Select your difficulty

Pick more than one for a sheet that mixes them.

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Excluded Values

Date Period

Find the excluded values.

  1. 4a−6a2−5a−84
  2. −y−2y2+11y+30
  3. 3m−6m2−3m−4
  4. 9b+5b2−10b+21
  5. 6b−2b2+3b−10
  6. 4n−9n2−10n−11
  7. 2m+8m2−21m+108
  8. −7x+7x2−11x+28
  9. −6y−4y2+17y+60
  10. −9v−2v2−12v+11
  11. −3b−2b2+4b−32
  12. −9a−8a2−9a+14
  13. 8y+3y2−1
  14. −4x−1x2+x−110
  15. 3v+6v2+22v+121
  16. −m+2m2+15m+36
  17. 5x+3x2−3x−10
  18. −2p+8p2+2p−35
  19. −4a+6a2+5a−6
  20. −8a+2a2+5a−84

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

Sigma Prep · sigmaprep.io/worksheets

Name

Excluded ValuesAnswer keyVersion 1

Date Period

Find the excluded values.

  1. 4a−6a2−5a−84a≠−7,12
  2. −y−2y2+11y+30y≠−6,−5
  3. 3m−6m2−3m−4m≠−1,4
  4. 9b+5b2−10b+21b≠3,7
  5. 6b−2b2+3b−10b≠−5,2
  6. 4n−9n2−10n−11n≠−1,11
  7. 2m+8m2−21m+108m≠9,12
  8. −7x+7x2−11x+28x≠4,7
  9. −6y−4y2+17y+60y≠−12,−5
  10. −9v−2v2−12v+11v≠1,11
  11. −3b−2b2+4b−32b≠−8,4
  12. −9a−8a2−9a+14a≠2,7
  13. 8y+3y2−1y≠−1,1
  14. −4x−1x2+x−110x≠−11,10
  15. 3v+6v2+22v+121v≠−11
  16. −m+2m2+15m+36m≠−12,−3
  17. 5x+3x2−3x−10x≠−2,5
  18. −2p+8p2+2p−35p≠−7,5
  19. −4a+6a2+5a−6a≠−6,1
  20. −8a+2a2+5a−84a≠−12,7

Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep

How to do these

x+5x2−4x−12

  1. Only the bottom matters.
  2. x² - 4x - 12 factors as (x - 6)(x + 2).
  3. Each parenthesis set to zero gives a value to exclude.

The answer is x≠6,−2.

Where students go wrong

Looking at the top. The numerator can be anything at all, including zero: it is only the denominator that can break the expression. The other slip is canceling first, which hides the excluded value rather than removing it.

Also called restricted values, domain of a rational expression or undefined values.

Questions about these worksheets

Yes. Every excluded values sheet is free to print and free to download as a PDF. There is no account to make, no email to hand over and no limit on how many you take.

Yes. The answer key prints on a second page, and you can choose whether it shows each question beside its answer or just the answers in a list.

Yes. Print straight from the page, or download the PDF and print that. The sheet is laid out for paper rather than squeezed off a screen, so there is room to work under each question, and the answer key comes out on its own page.

Algebra 1 is usually taken around 8th or 9th grade, though schools vary and plenty of students meet it earlier or later. Pick the difficulty rather than the grade: the easy level suits a first lesson on it, the hard level suits review before a test.

Yes, as many as you like. The questions are built fresh each time rather than picked from a fixed set of files, so pressing Generate gives a new sheet. That is what you want for a second class, a retake, or two students sitting next to each other.

That is the closest comparison, and Kuta Software is good software. It is also paid software you install on a computer. These worksheets run in a browser tab for free, with no account and nothing to install. Like Kuta, the excluded values questions are generated when you ask for them rather than pulled from a fixed set of files, so two classes never get the same sheet, and the answer key comes with it.

Yes. There are two levels, and you can tick more than one for a sheet that mixes them, in which case the questions come out easiest first. The harder levels are not just larger numbers: they ask for something the easy ones do not.

Looking at the top. The numerator can be anything at all, including zero: it is only the denominator that can break the expression. The other slip is canceling first, which hides the excluded value rather than removing it.