WJEC Unit 1 2022 June — Question 7 11 marks

Exam BoardWJEC
ModuleUnit 1 (Unit 1)
Year2022
SessionJune
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCircles
TypeLine-circle intersection points
DifficultyStandard +0.3 This is a standard multi-part circle geometry question requiring completing the square, solving simultaneous equations with a line and circle, finding perpendicular distances, and calculating a segment area. All techniques are routine for AS-level, though the multi-step nature and segment area calculation elevate it slightly above average difficulty.
Spec1.02q Use intersection points: of graphs to solve equations1.03d Circles: equation (x-a)^2+(y-b)^2=r^21.03e Complete the square: find centre and radius of circle

A circle \(C\) has centre \(A\) and equation \(x^2 + y^2 - 4x - 6y = 3\).
  1. Find the coordinates of \(A\) and the radius of \(C\). [3]
The line \(L\) with equation \(y = x + 5\) intersects \(C\) at the points \(P\) and \(Q\).
  1. Determine the coordinates of \(P\) and \(Q\). [4]
  2. The point \(B\) is on \(PQ\) and is such that \(AB\) is perpendicular to \(PQ\). Find the length of \(PB\). [2]
  3. Show that the area of the smaller segment enclosed by \(C\) and \(L\) is \(4\pi - 8\). [2]

A circle $C$ has centre $A$ and equation $x^2 + y^2 - 4x - 6y = 3$.

\begin{enumerate}[label=(\alph*)]
\item Find the coordinates of $A$ and the radius of $C$. [3]
\end{enumerate}

The line $L$ with equation $y = x + 5$ intersects $C$ at the points $P$ and $Q$.

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Determine the coordinates of $P$ and $Q$. [4]
\item The point $B$ is on $PQ$ and is such that $AB$ is perpendicular to $PQ$. Find the length of $PB$. [2]
\item Show that the area of the smaller segment enclosed by $C$ and $L$ is $4\pi - 8$. [2]
\end{enumerate}

\hfill \mbox{\textit{WJEC Unit 1 2022 Q7 [11]}}