(x+a)(x+b): Error Analysis & Misconceptions

Mathematics
Grade 8
11 questions
~22 mins
1 views0 downloads

About This Worksheet

A worksheet focusing on understanding, applying, and correcting errors related to expanding (x + a)(x + b). It includes practice, reasoning, real-world contexts, and extension problems.

Worksheet Preview

Full preview • 11 questions

(x+a)(x+b): 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.
Expand the expression (x + 3)(x + 5) using the FOIL method.
[2 marks]
2.
What is the product of (x - 2)(x + 4)?
[2 marks]
3.
Expand (x + a)(x + b) where a=2 and b=7. Write your answer in standard form.
[2 marks]
B

Error Analysis & Misconceptions

Study the common mistakes shown below. Identify what is wrong and correct the errors.
1.
Student's Work: (x + 4)(x + 6) = x^2 + 24. Identify the mistake and provide the correct expansion.
[3 marks]
2.
A student expands (x + 1)(x + 3) as x^2 + 3x + 1. What is the error? Fix it.
[3 marks]
C

Problem Solving & Reasoning

Solve the following problems and explain your reasoning.
1.
If (x + a)(x + b) = x^2 + (a + b)x + ab, explain why this is true for all real numbers a and b.
[4 marks]
2.
Solve for x: (x + 2)(x + 4) = 0. Show your working.
[3 marks]
D

Real-world Applications

Apply your knowledge to the following word problems.
1.
A rectangular garden has sides of length (x + 3) meters and (x + 5) meters. Write an expression for its area and expand it.
[3 marks]
E

Challenge & Extension

Tackle these advanced problems to extend your understanding.
1.
Expand (x + a)(x + b) and then factor the resulting quadratic expression. Discuss the conditions under which it can be factored easily.
[4 marks]
F

Mixed Review

Answer a variety of questions to review your understanding.
1.
Rewrite the expansion of (x + 1)(x + 2) in standard form.
[2 marks]
2.
Identify the error in expanding (x + 2)(x + 3) as x^2 + 6x + 5.
[3 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