Expressions, Equations and IdentitiesEdexcel GCSE Maths: Subtopic test
10 questions, 26 marks
Edexcel GCSE Maths
Expressions, Equations and Identities
Total 26 marks
Name
Class
Date
- 1A phone repair shop charges a call-out fee of £8 plus pounds for every minute of labour, where a repair takes minutes.(a)Which expression gives the cost, in pounds, of a repair taking minutes?[1 mark]
- A
- B
- C
- D
(b)Which of the following best describes the relationship , given that it is true only for one specific value of when the total cost is fixed at ?[1 mark]- AIt is an identity
- BIt is a formula with no variables
- CIt is an equation
- DIt is an expression
(c)If , simplify the expression for the total cost, , by collecting like terms with another repair that costs for a longer job with extra labour minutes added twice.[1 mark]- A
- B
- C
- D
Total for question 1: 3 marks
- 2A gardener is designing a rectangular flower bed. One side has length metres and the perpendicular side has length metres, so the area, , in square metres, is given by .(a)Write down the term in that results from expanding , and simplify the full expansion.[2 marks](b)The gardener increases both dimensions so the area becomes . Expand and fully simplify this expression for in terms of .[2 marks]
Total for question 2: 4 marks
- 3A factory manager models the number of faulty items produced per batch, , using algebraic expressions in terms of the batch size, , measured in hundreds of items.(a)A factory manager writes the number of faulty items produced per batch as , where is the batch size in hundreds. Factorise this expression fully.[3 marks](b)For a different production line, the manager models faults using . Show that this expression can be written as , and state which factorising technique you have used.[3 marks]
Total for question 3: 6 marks
- 4A maths teacher sets a worksheet on expressions, equations and identities to check whether her class understands the difference between simplifying, solving and proving.(a)A teacher asks two students to simplify the expression . Show full working to fully expand and simplify this expression, giving your answer in the form .[4 marks](b)One student claims that is an identity, true for every value of . Verify this claim by expanding and simplifying the left-hand side, and state whether the student is correct, explaining your reasoning.[4 marks](c)The teacher then asks the class to prove that the sum of any three consecutive integers is always a multiple of . Using , and to represent the three consecutive integers, prove this result using algebra, showing every step clearly.[5 marks]
Total for question 4: 13 marks
End of questions