About this worksheet

This free Year 7 area of triangles worksheet is written for the Western Australian curriculum and mapped to SCSA content description WA7MMGTW1. It targets one skill so students can practise until it sticks: by the end, students can say “I can find the area of any triangle using the base and perpendicular height, and work backwards to find a missing length.”

What’s inside

• Key idea box – a short explanation with worked examples to read before starting.
• A · Fluency (16 questions) – quick practice to build accuracy.
• B · Core (10 questions) – worded problems set in everyday Australian contexts.
• C · Reasoning (4 questions) – explain, justify and spot the error.
• D · Challenge (4 questions) – harder multi-step and problem-solving questions for students ready to stretch.
• Separate marking key – every answer with working, plus mark allocations and marking criteria for reasoning questions.

Skills covered

• Using A = ½ × base × perpendicular height
• Finding the height of right-angled and obtuse triangles
• Working backwards to find a missing base or height

How to use this worksheet

Start with the Key idea box, then complete Section A without a calculator. Most students should attempt Sections B and C; Section D suits students aiming for the top of the class or preparing for accelerated or extension maths. The worksheet is marked out of 58, and the score box on the last page helps students see which section needs more practice.

Common mistakes to watch for

• Using the sloping side as the height
• Forgetting to halve
• Missing a height that falls outside the triangle
• Leaving out square units

Where this fits in the WA Year 7 sequence

Area of Triangles sits in the Two-dimensional space and structures sub-strand of Measurement and geometry. It is one of a set of short, single-skill EduLift worksheets that split each Year 7 content description into sub-skills. Use the previous and next links to work through the sequence in order.

Common errors we see in tutoring

• Using the sloping side as the height
• Forgetting to halve
• Missing a height that falls outside the triangle
• Leaving out square units