AQA AS Paper 1 2021 June — Question 4 9 marks

Exam BoardAQA
ModuleAS Paper 1 (AS Paper 1)
Year2021
SessionJune
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicStraight Lines & Coordinate Geometry
TypeRectangle or parallelogram vertices
DifficultyModerate -0.3 This is a standard coordinate geometry question requiring routine techniques: finding gradients, perpendicular/parallel line equations, distance formula, and trapezium area. While it has multiple parts (9 marks total), each step follows directly from the previous with no novel insight required. The 'show that' in part (a)(ii) provides the answer, reducing problem-solving demand. Slightly easier than average due to its structured, procedural nature.
Spec1.02b Surds: manipulation and rationalising denominators1.03a Straight lines: equation forms y=mx+c, ax+by+c=01.03b Straight lines: parallel and perpendicular relationships

\(ABCD\) is a trapezium where \(A\) is the point \((1, -2)\), \(B\) is the point \((7, 1)\) and \(C\) is the point \((3, 4)\) \(DC\) is parallel to \(AB\). \(AD\) is perpendicular to \(AB\).
    1. Find the equation of the line \(CD\). [2 marks]
    2. Show that point \(D\) has coordinates \((-1, 2)\) [3 marks]
    1. Find the sum of the length of \(AB\) and the length of \(CD\) in simplified surd form. [2 marks]
    2. Hence, find the area of the trapezium \(ABCD\). [2 marks]

Question 4:

AnswerMarks Guidance
4(a)(i)Uses coordinates of A and B to
find gradient of AB3.1a M1
3 1
Equation is y – 4 =
6 2
1
2y = x + 5
2(𝑥𝑥−3)
Obtains correct equation of CD
AnswerMarks Guidance
(any form)1.1b A1
Subtotal2
QMarking instructions AO

AnswerMarks Guidance
4(a)(ii)Uses perpendicular gradients
property.1.1a M1
−1
Grad AB
Equation is y + 2 =
y = –2x
−2(𝑥𝑥−1)
Intersect at (–1, 2) = D
Obtains correct equation of AD
using their gradient (any form)
Or shows that A to (-1, 2) has
AnswerMarks Guidance
required gradient of -21.1b A1F
Obtains correct coordinates of D
Or shows that C to (-1,2) has
required gradient of 0.5
Or shows that (-1, 2) lies on
AnswerMarks Guidance
both lines1.1b A1
Subtotal3
QMarking instructions AO

AnswerMarks Guidance
4(b)(i)Calculates length of AB and CD.
At least one correct.1.1a M1
CD = √(4 + 16) = √20 = 2√5
AB + CD = 5√5
AnswerMarks Guidance
Obtains correct simplified sum1.1b A1
Subtotal2
QMarking instructions AO

AnswerMarks Guidance
4(b)(ii)Calculates AD and applies
trapezium area formula1.1a M1
= (5√5 2√5)
1
2 ×
= 25
AnswerMarks Guidance
Obtains correct area1.1b A1
Subtotal2
Question Total9
QMarking instructions AO
Question 4:
--- 4(a)(i) ---
4(a)(i) | Uses coordinates of A and B to
find gradient of AB | 3.1a | M1 | Grad AB = = = Grad DC
3 1
Equation is y – 4 =
6 2
1
2y = x + 5
2(𝑥𝑥−3)
Obtains correct equation of CD
(any form) | 1.1b | A1
Subtotal | 2
Q | Marking instructions | AO | Marks | Typical solution
--- 4(a)(ii) ---
4(a)(ii) | Uses perpendicular gradients
property. | 1.1a | M1 | Grad DA = = –2
−1
Grad AB
Equation is y + 2 =
y = –2x
−2(𝑥𝑥−1)
Intersect at (–1, 2) = D
Obtains correct equation of AD
using their gradient (any form)
Or shows that A to (-1, 2) has
required gradient of -2 | 1.1b | A1F
Obtains correct coordinates of D
Or shows that C to (-1,2) has
required gradient of 0.5
Or shows that (-1, 2) lies on
both lines | 1.1b | A1
Subtotal | 3
Q | Marking instructions | AO | Marks | Typical solution
--- 4(b)(i) ---
4(b)(i) | Calculates length of AB and CD.
At least one correct. | 1.1a | M1 | AB = √(36 + 9) = √45 = 3√5
CD = √(4 + 16) = √20 = 2√5
AB + CD = 5√5
Obtains correct simplified sum | 1.1b | A1
Subtotal | 2
Q | Marking instructions | AO | Marks | Typical solution
--- 4(b)(ii) ---
4(b)(ii) | Calculates AD and applies
trapezium area formula | 1.1a | M1 | AD = √(4 + 16) = √20 = 2√5
= (5√5 2√5)
1
2 ×
= 25
Obtains correct area | 1.1b | A1
Subtotal | 2
Question Total | 9
Q | Marking instructions | AO | Marks | Typical solution
$ABCD$ is a trapezium where $A$ is the point $(1, -2)$, $B$ is the point $(7, 1)$ and $C$ is the point $(3, 4)$

$DC$ is parallel to $AB$.

$AD$ is perpendicular to $AB$.

\begin{enumerate}[label=(\alph*)]
\item \begin{enumerate}[label=(\roman*)]
\item Find the equation of the line $CD$.
[2 marks]

\item Show that point $D$ has coordinates $(-1, 2)$
[3 marks]
\end{enumerate}

\item \begin{enumerate}[label=(\roman*)]
\item Find the sum of the length of $AB$ and the length of $CD$ in simplified surd form.
[2 marks]

\item Hence, find the area of the trapezium $ABCD$.
[2 marks]
\end{enumerate}
\end{enumerate}

\hfill \mbox{\textit{AQA AS Paper 1 2021 Q4 [9]}}