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Edexcel GCSE Maths (Non-calculator) Smart practice A mixed round aimed at your weak spots
Unit 1
Number
Unit 2
Algebra
Unit 3
Ratio, proportion and rates of change
Unit 4
Geometry and measures
Unit 5
Probability
Unit 6
Statistics
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Expanding, factorising and simplifying

Practise 36 exam-style questions on Expanding, factorising and simplifying for Edexcel GCSE Maths (Non-calculator). Write your answer as you would in the exam and get it marked in seconds against the mark scheme, point by point, with an AI tutor on hand if you get stuck.

  • 36 questions
  • 1–5 marks each
  • Instant marking
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20 questions, marked as you go

Sample questions with model answers

Here are 4 of the questions in this topic, each with a model answer, an explanation of why it earns the marks and the mark scheme an examiner would use.

Question 1

2 marks

Expand and simplify \(5(2y + 3) - 3(y - 4)\)

Model answer

\(5(2y + 3) - 3(y - 4) = 10y + 15 - 3y + 12 = 7y + 27\)

Explanation

Multiply every term inside each bracket by the number outside. The second bracket is multiplied by \(-3\), so \(-3 \times -4 = +12\). Writing \(-12\) here is the most common mistake.

Mark scheme
  1. 1 mark

    M1 for expanding both brackets with at most one error, e.g. \(10y + 15 - 3y + 12\)

    correct answer with no working scores full marks

  2. 1 mark

    A1 for \(7y + 27\)

    cao

Question 2

2 marks

Simplify \(\dfrac{12x^5y^3}{4x^2y^7}\)

Model answer

\(12 \div 4 = 3\)
\(x^5 \div x^2 = x^3\)
\(y^3 \div y^7 = y^{-4} = \dfrac{1}{y^4}\)
So the expression simplifies to \(\dfrac{3x^3}{y^4}\)

Explanation

Divide the numbers and subtract the indices for each letter separately. For \(y\), \(3 - 7 = -4\), and a negative index means the power goes to the denominator. Writing \(y^4\) on top is a common slip.

Mark scheme
  1. 2 marks

    B2 for \(\dfrac{3x^3}{y^4}\)

    oe, e.g. \(3x^3y^{-4}\); B1 for two of the three parts correct, e.g. \(3x^3y^4\), \(\dfrac{3x^3}{y^{10}}\) or \(\dfrac{8x^3}{y^4}\)

Question 3

3 marks

Simplify fully \(\dfrac{2x^2 + 5x - 3}{4x^2 - 1}\)

Model answer

\(2x^2 + 5x - 3 = 2x^2 + 6x - x - 3 = (2x - 1)(x + 3)\)
\(4x^2 - 1 = (2x + 1)(2x - 1)\)
\(\dfrac{(2x - 1)(x + 3)}{(2x + 1)(2x - 1)} = \dfrac{x + 3}{2x + 1}\)

Explanation

The denominator is a difference of two squares, which tells you that \((2x + 1)\) or \((2x - 1)\) is likely to be a factor of the numerator too. Factorise both, then cancel the common factor \((2x - 1)\).

Mark scheme
  1. 1 mark

    M1 for factorising the numerator, \((2x - 1)(x + 3)\)

    correct answer with no working scores full marks

  2. 1 mark

    M1 for factorising the denominator, \((2x + 1)(2x - 1)\)

  3. 1 mark

    A1 for \(\dfrac{x + 3}{2x + 1}\)

    cao

Question 4

4 marks

\(x\) and \(y\) are numbers such that
\[\frac{2^x \times 8^y}{4^x} = 2^5\]
and
\[x + y = 7\]

Work out the value of \(x\) and the value of \(y\).

Model answer

\(\dfrac{2^x \times 2^{3y}}{2^{2x}} = 2^{x + 3y - 2x} = 2^{3y - x}\)
So \(3y - x = 5\)
Add \(x + y = 7\): \(4y = 12\), so \(y = 3\)
\(x = 7 - 3 = 4\)

Explanation

Write every number as a power of 2, then use the index laws: add indices when multiplying and subtract when dividing. Comparing indices gives a second equation, which you solve with \(x + y = 7\). Check: \(\dfrac{16 \times 512}{256} = 32 = 2^5\).

Mark scheme
  1. 1 mark

    M1 for writing \(8^y = 2^{3y}\) or \(4^x = 2^{2x}\)

    correct answer with no working scores full marks

  2. 1 mark

    M1 for \(x + 3y - 2x = 5\) or \(3y - x = 5\)

    oe

  3. 1 mark

    M1 for a correct method to solve their two equations simultaneously

    e.g. adding to get \(4y = 12\)

  4. 1 mark

    A1 for \(x = 4\) and \(y = 3\)

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