[scheduled_pt_1:: 2025-01-10]
[scheduled:: 2025-01-13]

Word Problem Strategies

Concept summary and connections

part 1

part 2

Worked examples

  1. let x = the number of jelly donuts sold
  2. let y = the number of plain donuts sold
x+y=90given7x=money from jelly donutsgiven4y=money from plain donutsgiven7x+4y=399given, total is sum of parts from each kindy=90−xsubtraction Property of Equality, from (2)7x+4(90−x)=399substitution property of equality7x+360−4x=399distributive property3x=39subtraction property of equalityx=13 jelly donutsdivision property of equality13+y=90substitution property of equalityy=73 plain donutssubtraction property of equality

How to solve problems!

  1. Identify what the unknowns are that you're trying to resolve. What do you want to know? What will the answer have?
  2. Identify all of the data from the problem and write it down
  3. What relationships (equations) can I find that connect parts of the data?
    1. Write down equations that connect the data from the problem to your uknowns!
    2. You're not done with this step until you have used all of the data in a way that connects it to the unknowns, or until you have a clear path to the solution. Sometimes there's bogus extra data you don't need, so once you can see the solution you are done.
  4. Now connect the equations you discovered in order to find a solution. Remember that equations with two variables that aren't raised to powers are always going to give you lines, and there are three ways that multiple lines can interact:
    1. They can cross at one point, which is when you have a single solution
    2. The can be parallel and overlapping, which is when you have infinite solutions
    3. They can be parallel and separate, which is when there are no solutions.

Media resources

Guided practice

Homework