Question

I will send a pic of the 2nd drop down menu I don’t understand this

Answer 1

Given:

Radius of circle is 4

Sol:.

In triangle ABC is a right angle triangle:

Use pythagoras theorem then:

$\begin{gathered} \text{base}^2+perpendicular^2=hypotenus^2 \\ 4^2+4^2=CB^2^{} \\ 32=CB^2 \\ CB=\sqrt[]{32} \end{gathered}$

Area of triangle is:

$\begin{gathered} =\frac{1}{2}\times base\times height \\ =\frac{1}{2}\times4\times4 \\ =8 \end{gathered}$

Perimeter of circle is:

$\begin{gathered} =2\pi r \\ =2\times3.14\times4 \\ =25.12 \end{gathered}$

Length of CDB is:

$\begin{gathered} =25.12-\frac{25.12}{4} \\ =25.12-6.28 \\ =18.84 \end{gathered}$

Perimeter of figure.

$\begin{gathered} =\text{CDB}+CB \\ =18.84+5.656 \\ =24.50 \end{gathered}$

Area of figure.

Area of circle:

$\begin{gathered} =\pi r^2 \\ =3.14(4)^2 \\ =16\times3.14 \\ =50.24 \end{gathered}$

Area of CDB is:

$\begin{gathered} =50.24-\frac{50.24}{4} \\ =50.24-12.56 \\ =37.68 \end{gathered}$

Area of figure:

$\begin{gathered} \text{CDB area+ area of triangle} \\ =37.68+8 \\ =45.68 \end{gathered}$

Perimeter of figure is 24.50 and area of figure 45.68.