The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Mark this measurement down as a. Example: a = 2 cm
Note that this step calculates the area of one side of the cube. Example: a = 2 cm a2 = 2 x 2 = 4 cm2
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
For this formula, a equals the width of the prism, b equals the height, and c equals the length. Breaking down the formula, you can see that you are simply adding up all of the areas of each face of the object. The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Measure the length of the base to determine the length of the prism, and assign this to c. Example: c = 5 cm Measure the width of the base to determine the width of the prism, and assign this to a. Example: a = 2 cm Measure the height of the side to determine the height of the prism, and assign this to b. Example: b = 3 cm
Example: 2 x (a x c) = 2 x (2 x 5) = 2 x 10 = 20 cm2
Example: 2 x (a x b) = 2 x (2 x 3) = 2 x 6 = 12 cm2
Example: 2 x (b x c) = 2 x (3 x 5) = 2 x 15 = 30 cm2
Example: Surface Area = 2ab + 2bc + 2ac = 12 + 30 + 20 = 62 cm2.
For this formula, A is the area of a triangle which is A = 1/2bh where b is the base of the triangle and h is the height. P is simply the perimeter of the triangle which is calculated by adding all three sides of the triangle together. The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
The base, b, equals the length of the bottom of the triangle. Example: b = 4 cm The height, h, of the triangular base equals the distance between the bottom edge and the top peak. Example: h = 3 cm Area of the one triangle multiplied by 2= 2(1/2)bh = bh = 4*3 =12 cm
Example: H = 5 cm The three sides refer to the three sides of the triangular base. Example: S1 = 2 cm, S2 = 4 cm, S3 = 6 cm
Example: P = S1 + S2 + S3 = 2 + 4 + 6 = 12 cm
Example: P x H = 12 x 5 = 60 cm2
Example: 2A + PH = 12 + 60 = 72 cm2.
For this formula, r equals the radius of the sphere. Pi, or π, should be approximated to 3. 14. The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Example: r = 3 cm
Example: r2 = r x r = 3 x 3 = 9 cm2
Example: π*r2 = 3. 14 x 9 = 28. 26 cm2
Example: 4π*r2 = 4 x 28. 26 = 113. 04 cm2
2π*r2 represents the surface area of the two circular ends while 2πrh is the surface area of the column connecting the two ends. The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Example: r = 3 cm Example: h = 5 cm
Example: Area of base = πr2 = 3. 14 x 3 x 3 = 28. 26 cm2 Example: 2πr2 = 2 x 28. 26 = 56. 52 cm2
Example: 2π*rh = 2 x 3. 14 x 3 x 5 = 94. 2 cm2
Example: 2πr2 + 2πrh = 56. 52 + 94. 2 = 150. 72 cm2
For this equation, s refers to the length of each side of the square base and l refers to the slant height of each triangular side. The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Example: l = 3 cm Example: s = 1 cm
Example: s2 = s x s = 1 x 1 = 1 cm2
Example: 2 x s x l = 2 x 1 x 3 = 6 cm2
Example: s2 + 2sl = 1 + 6 = 7 cm2
The units of surface area will be some unit of length squared: in2, cm2, m2, etc.
Example: r = 2 cm Example: h = 4 cm
Example: l = √ (r2 + h2) = √ (2 x 2 + 4 x 4) = √ (4 + 16) = √ (20) = 4. 47 cm
Example: π*r2 = 3. 14 x 2 x 2 = 12. 56 cm2
Example: π*rl = 3. 14 x 2 x 4. 47 = 28. 07 cm
Example: πr2 + πrl = 12. 56 + 28. 07 = 40. 63 cm2
