Isosceles: Error Analysis & Misconceptions

Mathematics
Grade 8
12 questions
~24 mins
1 views0 downloads

About This Worksheet

A worksheet focused on understanding and identifying common misconceptions about Isosceles triangles, designed for Grade 8 students.

Worksheet Preview

Full preview • 12 questions

Isosceles: Error Analysis & Misconceptions

Subject: MathematicsGrade: Grade 8
Name:
Date:
TeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizzTeachWhizz

Untitled Worksheet

Grade Grade 8
A

Fluency & Practice

Answer all questions. Show your working in the grid spaces provided.
1.
In triangle ABC, sides AB and AC are equal. If AB = 7 cm, what is the length of AC?
[2 marks]
2.
Construct an isosceles triangle with two sides of 5 cm and a base of 8 cm. Label the vertices.
[3 marks]
3.
Calculate the measure of the vertex angle if the two equal sides are 6 cm each and the base is 10 cm.
[2 marks]
4.
Plot the graph of y=2x for x values from 0 to 5 on the grid.
[2 marks]
B

Problem Solving & Reasoning

Answer all questions. Provide explanations where required.
1.
A triangle has two equal sides of 9 cm each, and the base is 12 cm. Is the triangle necessarily isosceles? Explain your reasoning.
[3 marks]
2.
Given an isosceles triangle with equal sides of 8 cm each, and a vertex angle of 40°, find the length of the base using the Law of Cosines.
[3 marks]
3.
Explain why all equilateral triangles are also isosceles, but not all isosceles triangles are equilateral.
[2 marks]
C

Real-world Applications

Answer all questions with reasoning.
1.
A designer is creating a symmetric decorative triangle for a building facade. The two sides are 4 m each, and the base is 6 m. Determine if the triangle is isosceles and if it fits the design assumptions.
[3 marks]
D

Challenge & Extension

Attempt these more challenging problems.
1.
Construct an isosceles triangle where the base is 10 cm, and each of the equal sides is 13 cm. Find the measure of the vertex angle and verify using geometric properties.
[3 marks]
2.
A triangle has sides of 7 cm, 7 cm, and 10 cm. Is it isosceles? Justify your answer with calculations.
[2 marks]
E

Mixed Review & Error Analysis

Identify the common misconceptions, errors, or misconceptions in the following questions and correct them.
1.
A student states that in an isosceles triangle, the base angles are always equal, but the vertex angle can be different. Is this correct? Explain why or why not.
[3 marks]
2.
A diagram shows an isosceles triangle with unequal sides labeled as 5 cm and 8 cm. Identify and explain the mistake.
[2 marks]

Quick Actions

What is Remix?

Create a new worksheet based on this one. Change the grade level, topic, number of questions, or difficulty - then generate a fresh version.

  • • Change grade level (Grade 6 → Grade 7)
  • • Swap topics (Harry Potter → Macbeth)
  • • Add more questions (10 → 15)
  • • Adjust difficulty

Details

Created
1/1/2026
Updated
1/1/2026
Type
worksheet