FORESTHILL · INTEGRATED MATH 1 · ELO C3

Topic 29 Elimination Studio

Take your time. Nothing advances on a timer.

FOR STUDENTS AND PARENTS

Read one step together.

The explanations are here. You do not need to supply the algebra.

  1. Have paper and a pencil ready. The matching worksheet is optional. On blank paper, label your practice problems (a), (b), and (c).
  2. Start with Example A. Follow the green button. It tells you what comes next. Back revisits a step; nothing moves on a timer.
  3. Look at what changed. Ask, “What did we multiply? Did every term and the other side get the same multiplier?” Each screen explains its change.
  4. Give the student the pencil. In “Your turn,” let the student try before opening a hint or a worked route. A different correct route can work.
  5. When an answer differs, check each line. Look at the copied signs and each multiplication. The worked route shows one valid method. A different method can be correct if its steps are valid and its pair passes both original checks.
Quick meanings of the math words
Linear system
Here, two linear equations using the same unknown numbers x and y. We need values that make both true.
Term
A piece added or subtracted, with its sign: −2x and +7y are the terms on the left of the first equation.
Coefficient
The number multiplying a variable. In −2x, the coefficient is −2.
Opposite terms
Same variable and size, opposite signs: −4x and +4x. Together they equal 0.
Multiplier
The number we multiply by. Apply it to every term on both sides of an equation.
Elimination
Add prepared equations so one variable’s terms cancel. Then only one unknown remains.
Ordered pair
(x, y), with x first. Check those same values in both original equations.

Paper pause holds your place while you write. Use the section buttons to revisit a section; it keeps your last step. Refreshing keeps the lesson position when browser storage is available, but hides practice answers. Tab moves between controls; Enter or Space activates a button; Escape closes a window. Full screen is optional.

TAKE YOUR TIME

Your place is held.

Keep equal signs aligned. Show changes to both sides. Explain how you know.

KEEP THE STARTING EQUATIONS

Original equations

We use either original to find the second value. We check the final pair in both originals.

OPTIONAL · AFTER THE WORKED EXAMPLES

Which multipliers make opposites?

Change a multiplier. Every term and the right side change together. A multiplier of 1 leaves an equation unchanged.

Start the lesson over?

This resets the saved place and hides practice hints and answers. Your work on paper stays with you.