The area of a semicircle is 39.25 square metres. What is the semicircle's diameter?

The area of a semicircle is given by the formula A = 1/2 * π * r², where r is the radius of the semicircle.

Given that the area A is 39.25 square metres, we can set up the equation 39.25 = 1/2 * π * r².

To solve for r, we first multiply both sides of the equation by 2 to get rid of the 1/2 on the right side: 2 * 39.25 = π * r².

This simplifies to 78.5 = π * r².

Next, we divide both sides of the equation by π to isolate r²: r² = 78.5 / π.

Taking the square root of both sides gives us the radius r: r = sqrt(78.5 / π).

Finally, since the diameter of a circle (or semicircle) is twice the radius, we multiply r by 2 to get the diameter: d = 2 * r.

So, the diameter of the semicircle is 2 * sqrt(78.5 / π).