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Learning pack · IGCSE handout

Simultaneous Equations

What's in this pack: printable worksheet PDF, matching answers PDF (IGCSE / Secure–Stretch practice). Two equations, two unknowns: elimination or substitution. Check by substituting back into both originals.

Resources at the top · full summary · videos with short notes below.

🎒 Resources in this pack

Jump straight to the printable files, or scroll to the summary and videos.

Scaffolded Learning Sheet — attempt the worksheet, then use the Answers for a full written solution.

Files: 23_simultaneous_equations_handout.pdf · 23_simultaneous_equations_handout_answers.pdf

Full topic summary

Two equations, two unknowns: elimination or substitution. Check by substituting back into both originals.

Key learning points

  • Elimination: make one coefficient match, then add/subtract.
  • Substitution: rearrange one equation and replace in the other.
  • Graphically: intersection of two lines.

Worked example 1 — Elimination

Solve x+y=7x+y=7, x−y=1x-y=1.

Working

x=4, y=3x=4,\ y=3

Add to eliminate yy.

Worked example 2 — Substitution

Solve y=2x+1y=2x+1, x+y=7x+y=7.

Working

x=2, y=5x=2,\ y=5

Substitute for yy.

Worked example 3 — Scaled elimination

Solve 2x+3y=122x+3y=12, x+y=5x+y=5.

Working

x=3, y=2x=3,\ y=2

Match coefficients, then subtract.

🎬 Topic videos

  • Beautiful Visual Explanation of Completing the Square

    Eddie Woo · 4 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Introduction to Matrices (1 of 3: Systems of Linear Equations)

    Eddie Woo · 5 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Math Antics - Basic Inequalities

    Math Antics · 13 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Is there an equation for a triangle?

    Stand-up Maths · 16 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • Why is there no equation for the perimeter of an ellipse‽

    Stand-up Maths · 21 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • Behold all-new equations for triangles!

    Stand-up Maths · 22 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

More Lower Secondary packs

Browse the hub Learning Packs & Summary, or open the compact Simultaneous Equations summary.