Question

can you please help me

Answer 1

The formula for the area of a circle is:

$A=\pi\cdot r^2$

also the diameter can be written in function of the radius

$D=2\cdot r$

from this equation we can find the radius

$r=\frac{D}{2}$

this transforms the formula for the area into

$\begin{gathered} A=\pi\cdot(\frac{D}{2})^2 \\ A=\frac{\pi}{4}\cdot D^2 \end{gathered}$

since the diameter is equal to 26cm, then the area will be

$\begin{gathered} A=\frac{\pi}{4}\cdot676cm^2 \\ A=169\pi(cm^2)\approx530.93cm^2 \end{gathered}$