Question

The number of centimetres in the circumference of a circle is double the number of square centimetres in the area. What is the diameter of that circle?

Answer 1

Step-by-step explanation:

let be radius r

now given

$2\pi \:r \: =2 \pi \: r ^{2} \\ r = 1cm \\ now \: diameter \: \: \: d = 2r \\ d = 2 \times 1 = 2cm$