1. 1
   A straight line $L$ has equation $y = 3x - 7$.

   (a)

   What is the gradient of line $L$?

   [1 mark]

   • A$\frac{1}{3}$
   • B$-7$
   • C$3$
   • D$7$

   (b)

   What is the $y$-intercept of line $L$?

   [1 mark]

   • A$3$
   • B$-7$
   • C$0$
   • D$7$

   (c)

   A second line $M$ is parallel to $L$. Which of these could be the gradient of $M$?

   [1 mark]

   • A$-\frac{1}{3}$
   • B$-3$
   • C$\frac{1}{3}$
   • D$3$

   Total for question 1: 3 marks

2. 2
   Line $P$ passes through the points $(1, 4)$ and $(3, 10)$.

   (a)

   Find the gradient of line $P$.

   [2 marks]

   (b)

   Hence find the equation of line $P$, giving your answer in the form $y = mx + c$.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   Line $Q$ has equation $y = 2x + 5$. Line $R$ is perpendicular to line $Q$ and passes through the point $(4, 1)$.

   (a)

   Find the gradient of line $R$.

   [3 marks]

   (b)

   Hence find the equation of line $R$, giving your answer in the form $y = mx + c$.

   [3 marks]

   Total for question 3: 6 marks

4. 4
   A company charges a fixed call-out fee plus a rate per hour for a plumbing job. The total cost, $C$ pounds, of a job lasting $h$ hours is given by a linear function of $h$. A job lasting 2 hours costs £70. A job lasting 5 hours costs £130.

   (a)

   Find the equation of the line giving $C$ in terms of $h$, in the form $C = mh + c$.

   [4 marks]

   (b)

   A second company charges according to $C = 25h + 15$. Find the number of hours, $h$, for which both companies charge the same amount.

   [4 marks]

   (c)

   The first company's manager claims that a 10-hour job would cost £250. Show that this claim is incorrect, and find the correct cost of a 10-hour job with this company.

   [5 marks]

   Total for question 4: 13 marks

End of questions