Finding: Surface Area of Triangular Prism 1 - Mr Kim
Finding: Surface Area of Triangular Prism 1
- Mr Kim
Surface Area of the following prisms will be explained in this
lesson
Starts from slide number 36
Example 1
9 m
16 m
11 m
12 m
9 m
16 m
11 m
12 m
This is a Triangular Prism
9 m
16 m
11 m
Triangular Prism has 5 faces
12 m
1
2
3
4
5
We must calculate the Total Area of all 5
Faces
9 m
16 m
11 m
12 m
9 m
16 m
11 m
12 m
Front Area is
9 m
16 m
11 m
12 m
Front Area is
21
Always times by a half
for Triangles
9 m
16 m
11 m
12 m
Front Area is
921
9 m
16 m
11 m
12 m
Front Area is
11921
9 m
16 m
11 m
12 m
Now, the Back Area is the same as the Front
so…
11921
9 m
16 m
11 m
12 m
211921
Now, the Back Area is the same as the Front
so times by 2
9 m
16 m12 m
11 m
Now we are going to find the Side Area
211921
9 m
16 m12 m
211921
11 m
Now we are going to find the Side Area
9 m
16 m12 m
211921
11 m
Make sure to add that on
The Side Area is a Rectangle so just multiply
the numbers
9 m
16 m12 m
211921
11 m
The Side Area is a Rectangle so just multiply
the numbers
9 m
16 m12 m
211921
11 m
16
The Side Area is a Rectangle so just multiply
the numbers
9 m
16 m12 m
211921
11 m
1216
9 m
16 m12 m
211921
11 m
But the other Side is the same as well so…
1216
9 m
16 m12 m
211921
11 m
But the other Side is the same as well so
times by 2
21216
9 m
16 m12 m
211921
11 m
Now we are going to find the Bottom Area
21216
9 m
16 m12 m
211921
11 m
21216
Now we are going to find the Bottom Area
9 m
16 m12 m
211921
11 m
21216
Make sure to add that on as well
9 m
16 m12 m
211921
11 m
The Bottom Area is a Rectangle as well so
just multiply the numbers
21216
9 m
16 m12 m
211921
11 m
21216
9
The Bottom Area is a Rectangle as well so
just multiply the numbers
9 m
16 m12 m
211921
11 m
21216
169
The Bottom Area is a Rectangle as well so
just multiply the numbers
9 m
16 m12 m
211921
11 m
Putting this altogether in the calculator
gives…
21216
169
9 m
16 m12 m
211921
11 m
Putting this altogether in the calculator
gives…
212162627169 m
Our Final Answer!
Example 2
7 cm
8 cm
12.5 cm
10.6 cm
7 cm
8 cm
12.5 cm
10.6 cm
Once again we need to calculate the Area of all
5 Faces
7 cm
8 cm
12.5 cm
10.6 cm
Front Area is
7 cm
8 cm
12.5 cm
10.6 cm
Front Area is
21
7 cm
8 cm
12.5 cm
10.6 cm
Front Area is
8721
7 cm
8 cm
12.5 cm
10.6 cm
And the Back Area is the same as the Front
so…
8721
7 cm
8 cm
12.5 cm
10.6 cm
28721
And the Back Area is the same as the Front
so times by 2
7 cm
8 cm
12.5 cm
10.6 cm
Now we are going to find the Right Side
Area
28721
7 cm
8 cm
12.5 cm
10.6 cm
Now we are going to find the Right Side
Area
28721
7 cm
8 cm
12.5 cm
10.6 cm
28721
Make sure to add that on
7 cm
8 cm
12.5 cm
10.6 cm
The Right Side is a Rectangle so just multiply
the numbers
28721
7 cm
8 cm
12.5 cm
10.6 cm
The Right Side is a Rectangle so just multiply
the numbers
28721
7 cm
8 cm
12.5 cm
10.6 cm
5.126.10
28721
The Right Side is a Rectangle so just multiply
the numbers
7 cm
8 cm
12.5 cm
10.6 cm
Now we are going to find the Left Side Area
5.126.10
28721
7 cm
8 cm
12.5 cm
10.6 cm
Now we are going to find the Left Side Area
28721
5.126.10
7 cm
8 cm
28721
5.126.1012.5 cm
10.6 cm
Make sure to add that on
7 cm
8 cm
12.5 cm
10.6 cm
The Left Side is a Rectangle as well
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
So the Left Side Area is
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
So the Left Side Area is
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
7
28721
5.126.10
So the Left Side Area is
7 cm
8 cm
12.5 cm
10.6 cm
So the Left Side Area is
7
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
7
28721
5.126.10
If it’s 12.5 cm there
7 cm
8 cm
12.5 cm
10.6 cm
7
It’s 12.5 cm there as well
28721
5.126.1012.5 cm
7 cm
8 cm
12.5 cm
10.6 cm
5.127
28721
5.126.10
It’s 12.5 cm there as well
12.5 cm
7 cm
8 cm
12.5 cm
10.6 cm
5.127
Now finally, we need to find the Bottom Area
12.5 cm
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
5.127
Now finally, we need to find the Bottom Area
12.5 cm
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
5.127
12.5 cm
28721
5.126.10
Make sure to add that on
7 cm
8 cm
12.5 cm
10.6 cm
The Bottom Area is a Rectangle as well so just
multiply the numbers
5.127
12.5 cm
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
The Bottom Area is a Rectangle as well so just
multiply the numbers
5.127
12.5 cm
28721
5.126.10
7 cm
8 cm
12.5 cm
10.6 cm
5.1275.128
12.5 cm
28721
5.126.10
The Bottom Area is a Rectangle as well so just
multiply the numbers
7 cm
8 cm
10.6 cm
5.1275.128
12.5 cm
Putting this altogether in the calculator
gives…
12.5 cm
28721
5.126.10
7 cm
8 cm
10.6 cm
5.1275.128
12.5 cm
Putting this altogether in the calculator
gives…
2376cmOur Final Answer!
12.5 cm
28721
5.126.10