## Thursday, March 18, 2010

### Surface Area Growing Post

Here is my Growing Post for Surface Area

RECTANGULAR PRISM :

Here is the formula to calculate the area of a rectangular prism
a = l x w
a = 2 x 8
a = 16cm²

a = l x w
a = 2 x 2
a = 4cm²

TSA

= (bigger rectangle)+(bigger rectangle)+(bigger rectangle)+(bigger rectangle)+( smaller rectangle) + (smaller rectangle)
= 16 + 16 + 16 + 16 + 4 + 4
= 72cm²

TRIANGULAR PRISM :

Here is the formula
to calculate the area of a triangular prism
a = b x h ÷ 2
a = 7 x 4 ÷ 2
a = 18cm²

Here is the formula to calculate the area of a rectangular prism
a = l x w
a = 3 x 7
a = 21cm²

a= l x w
a = 3 x 8
a = 24cm²

a= l x w
a= 3 x 4
a = 12cm²

TSA

= (triangle)+(triangle)+(rectangle)+(rectangle)+(rectangle)
= 18+18+21+24+12
= 73cm²

CYLINDER :

Here is the formula to calculate the radius
r = d ÷ 2
r = 6 ÷ 2
r = 3cm²

Here is the formula to calculate the area of a cylinder
sa = 2 x (pi x r²) + (pi x d x h)
sa = 2 x 3.14 x 3 x 3 + 3.14 x 6 x 7
sa = 56.52 + 131.88
sa = 188.4 cm²

So that's my " growing post " for " surface area " ... hope you liked it and feel free to comment. byee