Home More advice Education & School
How to find the area of a circle if you have the diameter?
the area of a circle is : radius squared, multiplied by π. I.e radius = half the diameter 14/2 = 7inches 7 squared = 7x7 = 49 π = 3.14
so Area = 49 x 3.14 =153.86 inches squared
this is how I'd do it but I aint the best at maths so people feel free to correct me =] hope I helped.
Ok, example: D= 7, if it says to put π as 3.14, youd 7 x 3.14, or if it says leave it as π, get a scientific calculator and type in 7 x π and hit equal... Im in 8th grade and know how to do it. A simple way to remember is π r ^2(π r (r= radius) squared)
area of a cricle is: Pi x r^2 and diameter is twice the radius
so, if you have diameter...u can divide it by 2 to get the radius and then plug it into the equation for area of a circle...easy peasy man
Pi are squared
so if you have the diameter divide by 2 square it then multiply by pi
e.g. diameter = 8
8/2 = 4 4 squared = 16 16 times pi = 50.256
uhm no guardian115, pi "r" sqared for D=7 would be 3.5 squared... not 7 times pi