โž• Algebra 1 ยท Systems of Equations

Systems Word Problems cheat sheet

Everything you need on one page. Print it, or switch on test-yourself mode to blur the answers and check your memory.

The plan (SOLVED)

  • S: Say what each variable means (units)
  • O: One equation for each fact
  • L: Look for the easiest method
  • V: Values: solve for both
  • E: Examine the answer in the story
  • D: Deliver a sentence with units

Translate

  • Count: (number of A) + (number of B) = total number
  • Value: (price A)(number A) + (price B)(number B) = total value
  • Plan: cost = fee + rate ร— amount
  • Distance = rate ร— time

Which method?

  • A variable is alone: substitution
  • Standard form: elimination
  • Want the picture: graph (confirm by substituting)

Special cases

  • False leftover, like 15ย = 9: never equal (no solution)
  • True leftover, like 0ย = 0: always equal (infinitely many)
  • Answer not whole or negative for a count: not viable

Watch out

  • Do not add tickets to dollars
  • Do not round a nonviable answer
  • Check the story, not just your equations

Formulas

  • Count equation: (number of A) + (number of B) = total number
  • Value equation: (price of A) ร— (number of A) + (price of B) ร— (number of B) = total value
  • Plan cost: cost = fixed fee + (rate) ร— (amount)
  • Distance: distance = rate ร— time

Systems Word Problems cheat sheet from HighSchoolQ.com, for personal study use.