It is difficult to explain how the formula for calculating the surface area of the sphere was discovered. Anyway, use the formula (4πr2) is really simple.
Steps
Step 1. Calculate the radius
If you know the diameter, divide it by 2 and you will have the radius measurement.
Find the Surface Area of a Sphere Step 1Bullet1
If you know the volume, divide by π, multiply by 3, divide by 4, and take the cube root.
Find the Surface Area of a Sphere Step 1Bullet2
Find the Surface Area of a Sphere Step 2
Step 2. Square it
That is, it multiplies by itself.
Find the Surface Area of a Sphere Step 3
Step 3. Multiply by 4
Find the Surface Area of a Sphere Step 4
Step 4. Multiply by π
If the problem requires the 'exact value' write the symbol π after your number and that's it. Alternatively use 3.14 or the π button on your calculator.
Example
r = 5
52=25
25×4=100
100π or 314, 2
Advice
If the radius includes the square root, such as √5, remember that the coefficient squares and the radical becomes regular. (3√5)2 becomes 9 × 5 which is 45.
Calculating the area of a polygon can be simple if it is a figure such as a regular triangle, or very complicated if you are dealing with an irregular shape with eleven sides. If you want to know how to calculate the area of polygons, follow these instructions.
The total surface of a geometric solid is given by the sum of the area of each of the faces that compose it. To calculate the area occupied by the surface of a cylinder, it is necessary to calculate the area of the two bases and add it to the area of the cylindrical section between them.
The surface of a solid is the sum of the extension of all the faces present outside it. The faces of a cube are all six congruent. Consequently, to find the total area of a cube, all you have to do is find the area of a single face of the cube and multiply it by six.
A sphere is a perfectly round three-dimensional geometric body, in which all points on the surface are equidistant from the center. Many commonly used objects, such as balloons or globes are spheres. If you want to calculate the volume you just have to find the radius and insert it in the simple formula:
Calculating the area of a square is a very simple operation, as long as you know some basic information, such as the length of one side, the perimeter or the length of the diagonal. Read on to find out how. Steps Method 1 of 3: Using the Length of a Side Step 1.
