How to Find Surface Area
Define the formula for surface area of a cube., Measure the length of one side., Square your measurement for a., Multiply this product by six.
Step-by-Step Guide
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Step 1: Define the formula for surface area of a cube.
A cube has six identical square sides.
Because both the length and width of a square are equal, the area of a square is a2, where a is the length of a side.
Since there are 6 identical sides of a cube, to find the surface area, simply multiply the area of one side times
6.
The formula for surface area (SA) of a cube is SA = 6a2, where a is the length of one side.The units of surface area will be some unit of length squared: in2, cm2, m2, etc. -
Step 2: Measure the length of one side.
Each side or edge of a cube should, by definition, be equal in length to the others, so you only need to measure one side.
Using a ruler, measure the length of the side.
Pay attention to the units you are using.
Mark this measurement down as a.
Example: a = 2 cm , Square the measurement taken for the length of the edge.
To square a measurement means to multiply it by itself.
When you are first learning these formulas, it might be helpful to write it as SA= 6*a*a.
Note that this step calculates the area of one side of the cube.
Example: a = 2 cm a2 = 2 x 2 = 4 cm2 , Remember, a cube has six identical sides.
Now that you have the area of one side, you need to multiply it by six to account for all six sides.
This step completes the calculation for the cube's surface area.
Example: a2 = 4 cm2 Surface Area = 6 x a2 = 6 x 4 = 24 cm2 -
Step 3: Square your measurement for a.
-
Step 4: Multiply this product by six.
Detailed Guide
A cube has six identical square sides.
Because both the length and width of a square are equal, the area of a square is a2, where a is the length of a side.
Since there are 6 identical sides of a cube, to find the surface area, simply multiply the area of one side times
6.
The formula for surface area (SA) of a cube is SA = 6a2, where a is the length of one side.The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Each side or edge of a cube should, by definition, be equal in length to the others, so you only need to measure one side.
Using a ruler, measure the length of the side.
Pay attention to the units you are using.
Mark this measurement down as a.
Example: a = 2 cm , Square the measurement taken for the length of the edge.
To square a measurement means to multiply it by itself.
When you are first learning these formulas, it might be helpful to write it as SA= 6*a*a.
Note that this step calculates the area of one side of the cube.
Example: a = 2 cm a2 = 2 x 2 = 4 cm2 , Remember, a cube has six identical sides.
Now that you have the area of one side, you need to multiply it by six to account for all six sides.
This step completes the calculation for the cube's surface area.
Example: a2 = 4 cm2 Surface Area = 6 x a2 = 6 x 4 = 24 cm2
About the Author
Kathleen Kim
Experienced content creator specializing in practical skills guides and tutorials.
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