a circle has an area of 1m squared. find its diameter.?

Question

i know how to do area and stuff, i just got stuck on this one. help? thanks.

Answer 1

Area = pi * r^2

So...

1 = pi * r^2

Divide both sides by pi:

1/pi = r^2

.318 = r^2

Square root both sides:

.564 = r

since the diameter is twice the radius, the diameter is approximately 1.12

Answer 2

We know the formula for the area of a circle:

A = πr²


and we are given A = 1 m², so

1 m² = πr²


We reverse the equation, so the r will be on the left...

πr² = 1 m²


We then divide both sides by π

r² = 1/π m²


Get the square root of both sides, and we get

r = √(1/π) m


Since the diameter is twice the radius, then

d = 2r = 2√(1/π) m


or approximately

d = 1.128379 m

Answer 3

The standard formula for the area of a circle is pi x r squared. Diameter d = 2r. So r = d/2. So A = pi x d squared/4. So 4A/pi = d squared. So d is equal to the square root of 4A/pi. Using A = 1m and pi = 3.14 gives d =1.13m.

Answer 4

Use your equation for area and work backwards.

Area = pi*(r^2)
r = sqrt(Area/pi)

Diameter = 2r = 2*sqrt(Area/pi)

plugging in 1 for Area gives Diameter = 1.13 or so.

Answer 5

A = π.r²
r² = 1 / π
r = √(1/π)
d = 2√(1/π)
d = 1.13 m (to 2 dec. places)

Answer 6

pid^2/4=1
d=sqrt(4/pi)
=1.13m

Answer 7

Do your own homework...