Sketch two modulus of linear functions and find intersection

Sketch graphs of two modulus functions where both expressions inside modulus are linear (e.g., y = |3x+2a| and y = |3x-4a|), find coordinates of intersection points, and possibly solve related equation or inequality.

11 questions · Moderate -0.1

Sort by: Default | Easiest first | Hardest first
CAIE P2 2020 June Q4
7 marks Moderate -0.3
4
  1. Sketch, on the same diagram, the graphs of \(y = | 3 x + 2 a |\) and \(y = | 3 x - 4 a |\), where \(a\) is a positive constant. Give the coordinates of the points where each graph meets the axes.
  2. Find the coordinates of the point of intersection of the two graphs.
  3. Deduce the solution of the inequality \(| 3 x + 2 a | < | 3 x - 4 a |\).
CAIE P2 2020 Specimen Q3
6 marks Moderate -0.8
3 It is g n th t \(a\) is a p itie co tan.
    1. Sketch sib ed ag am th g ad \(6 y = | 2 x - 3 a |\) ad \(y = | 2 x + 4 a |\).
    2. State th co dia tes
Edexcel P3 2021 January Q4
9 marks Moderate -0.3
4. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{624e9e2f-b6b8-47ce-accc-31dcd5f0554e-10_646_762_264_593} \captionsetup{labelformat=empty} \caption{Figure 2}
\end{figure} Figure 2 shows a sketch of the graph with equation \(y = \mathrm { f } ( x )\), where $$\mathrm { f } ( x ) = | 3 x + a | + a$$ and where \(a\) is a positive constant. The graph has a vertex at the point \(P\), as shown in Figure 2 .
  1. Find, in terms of \(a\), the coordinates of \(P\).
  2. Sketch the graph with equation \(y = g ( x )\), where $$g ( x ) = | x + 5 a |$$ On your sketch, show the coordinates, in terms of \(a\), of each point where the graph cuts or meets the coordinate axes. The graph with equation \(y = \mathrm { g } ( x )\) intersects the graph with equation \(y = \mathrm { f } ( x )\) at two points.
  3. Find, in terms of \(a\), the coordinates of the two points. \includegraphics[max width=\textwidth, alt={}, center]{624e9e2f-b6b8-47ce-accc-31dcd5f0554e-11_2255_50_314_34}
    VIXV SIHIANI III IM IONOOVIAV SIHI NI JYHAM ION OOVI4V SIHI NI JLIYM ION OO
Edexcel C34 2019 June Q6
7 marks Standard +0.3
6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{a9870c94-0910-46ec-a54a-44a431cb324e-14_988_1120_123_395} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} Figure 1 shows a sketch of the graph with equation \(y = | 4 x + 10 a |\), where \(a\) is a positive constant. The graph cuts the \(y\)-axis at the point \(P\) and meets the \(x\)-axis at the point \(Q\) as shown.
    1. State the coordinates of \(P\).
    2. State the coordinates of \(Q\).
  1. A copy of Figure 1 is shown on page 15. On this copy, sketch the graph with equation $$y = | x | - a$$ Show on the sketch the coordinates of each point where your graph cuts or meets the coordinate axes.
  2. Hence, or otherwise, solve the equation $$| 4 x + 10 a | = | x | - a$$ giving your answers in terms of \(a\). \begin{figure}[h]
    \includegraphics[alt={},max width=\textwidth]{a9870c94-0910-46ec-a54a-44a431cb324e-15_860_1128_447_392} \captionsetup{labelformat=empty} \caption{Figure 1}
    \end{figure} \(\_\_\_\_\) 7
OCR C3 Q8
10 marks Standard +0.3
8. The functions f and g are defined for all real values of \(x\) by $$\begin{aligned} & \mathrm { f } : x \rightarrow | x - 3 a | \\ & \mathrm { g } : x \rightarrow | 2 x + a | \end{aligned}$$ where \(a\) is a positive constant.
  1. Evaluate fg(-2a).
  2. Sketch on the same diagram the graphs of \(y = \mathrm { f } ( x )\) and \(y = \mathrm { g } ( x )\), showing the coordinates of any points where each graph meets the coordinate axes.
  3. Solve the equation $$\mathrm { f } ( x ) = \mathrm { g } ( x )$$
OCR C3 Q6
9 marks Standard +0.8
6. (i) Sketch on the same diagram the graphs of \(y = | x | - a\) and \(y = | 3 x + 5 a |\), where \(a\) is a positive constant. Show on your diagram the coordinates of any points where each graph meets the coordinate axes.
(ii) Solve the equation $$| x | - a = | 3 x + 5 a |$$
OCR MEI C3 Q3
6 marks Moderate -0.3
3 Fig. 1 shows the graphs of \(y = | x |\) and \(y = a | x + b |\), where \(a\) and \(b\) are constants. The intercepts of \(y = a | x + b |\) with the \(x\)-and \(y\)-axes are \(( - 1,0 )\) and \(\left( 0 , \frac { 1 } { 2 } \right)\) respectively. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{125b76c1-5ab3-4645-a3c4-cf167a04f453-1_617_950_909_582} \captionsetup{labelformat=empty} \caption{Fig. 1}
\end{figure}
  1. Find \(a\) and \(b\).
  2. Find the coordinates of the two points of intersection of the graphs.
OCR MEI C3 2013 June Q1
6 marks Moderate -0.3
1 Fig. 1 shows the graphs of \(y = | x |\) and \(y = a | x + b |\), where \(a\) and \(b\) are constants. The intercepts of \(y = a | x + b |\) with the \(x\)-and \(y\)-axes are \(( - 1,0 )\) and \(\left( 0 , \frac { 1 } { 2 } \right)\) respectively. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{28ce1bcc-e9d5-4ae6-98c0-67b5b8c50bc6-2_624_958_468_539} \captionsetup{labelformat=empty} \caption{Fig. 1}
\end{figure}
  1. Find \(a\) and \(b\).
  2. Find the coordinates of the two points of intersection of the graphs.
Edexcel Paper 2 2023 June Q12
10 marks Moderate -0.3
12. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{3f6f3f19-a1d0-488b-a1a4-302cc4cf5a1e-34_643_652_210_708} \captionsetup{labelformat=empty} \caption{Figure 2}
\end{figure} The number of subscribers to two different music streaming companies is being monitored. The number of subscribers, \(N _ { \mathrm { A } }\), in thousands, to company \(\mathbf { A }\) is modelled by the equation $$N _ { \mathrm { A } } = | t - 3 | + 4 \quad t \geqslant 0$$ where \(t\) is the time in years since monitoring began.
The number of subscribers, \(N _ { \mathrm { B } }\), in thousands, to company B is modelled by the equation $$N _ { \mathrm { B } } = 8 - | 2 t - 6 | \quad t \geqslant 0$$ where \(t\) is the time in years since monitoring began.
Figure 2 shows a sketch of the graph of \(N _ { \mathrm { A } }\) and the graph of \(N _ { \mathrm { B } }\) over a 5-year period.
Use the equations of the models to answer parts (a), (b), (c) and (d).
  1. Find the initial difference between the number of subscribers to company \(\mathbf { A }\) and the number of subscribers to company B. When \(t = T\) company A reduced its subscription prices and the number of subscribers increased.
  2. Suggest a value for \(T\), giving a reason for your answer.
  3. Find the range of values of \(t\) for which \(N _ { \mathrm { A } } > N _ { \mathrm { B } }\) giving your answer in set notation.
  4. State a limitation of the model used for company B.
Edexcel C3 Q6
10 marks Standard +0.8
6. (a) Sketch on the same diagram the graphs of \(y = | x | - a\) and \(y = | 3 x + 5 a |\), where \(a\) is a positive constant. Show on your diagram the coordinates of any points where each graph meets the coordinate axes.
(b) Solve the equation $$| x | - a = | 3 x + 5 a | .$$
AQA Paper 2 2021 June Q4
6 marks Moderate -0.8
4
  1. On Figure 1 add a sketch of the graph of $$y = | 3 x - 6 |$$ 4
  2. Find the coordinates of the points of intersection of the two graphs.
    Fully justify your answer. \includegraphics[max width=\textwidth, alt={}, center]{b7df05bf-f3fc-4705-a13c-6b562896fa9f-05_2488_1716_219_153}