Compound shape area

A question is this type if and only if it asks to find the area of a shape made from multiple sectors, triangles, or other regions combined.

27 questions · Standard +0.1

1.05d Radians: arc length s=r*theta and sector area A=1/2 r^2 theta
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Edexcel C2 Q7
12 marks Standard +0.3
\includegraphics{figure_3} Fig. 3 shows the cross-sections of two drawer handles. Shape \(X\) is a rectangle \(ABCD\) joined to a semicircle with \(BC\) as diameter. The length \(AB = d\) cm and \(BC = 2d\) cm. Shape \(Y\) is a sector \(OPQ\) of a circle with centre \(O\) and radius \(2d\) cm. Angle \(POQ\) is \(\theta\) radians. Given that the areas of the shapes \(X\) and \(Y\) are equal,
  1. prove that \(\theta = 1 + \frac{1}{4}\pi\). [5]
Using this value of \(\theta\), and given that \(d = 3\), find in terms of \(\pi\),
  1. the perimeter of shape \(X\), [2]
  2. the perimeter of shape \(Y\). [3]
  3. Hence find the difference, in mm, between the perimeters of shapes \(X\) and \(Y\). [2]
SPS SPS SM Pure 2021 June Q3
5 marks Moderate -0.8
\includegraphics{figure_1} The shape \(ABCDOA\), as shown in Figure 1, consists of a sector \(COD\) of a circle centre \(O\) joined to a sector \(AOB\) of a different circle, also centre \(O\). Given that arc length \(CD = 3\) cm, \(\angle COD = 0.4\) radians and \(AOD\) is a straight line of length 12 cm,
  1. find the length of \(OD\), [2]
  2. find the area of the shaded sector \(AOB\). [3]