the base of a prism is triangular in shape with side 3 cm 4 cm and 5 cm find the volume of prism if its height is 10 cm
Answers
Volume of prism = area of the triangular base × height
Answer :-
- The volume of prism = 60 cm³ .
Given :-
- The Base of a prism is in triangular shape
- Sides of the base given as 3 cm, 4 cm and 5 cm respectively.
- Prism height = 10 cm.
To Find :-
- Find the volume of the prism.
Solution :-
As we know ,
Volume of prism = Area of base × Height .
Height is already given as 10 cm
we need to find area first
For area, we need to know the sides , which is also given as :-
a = 3 cm
b = 4 cm
c = 5 cm
By using heron's formula :-
Finding the " s " { semi perimeter } first
Semi perimeter = ( a + b + c ) / 2
➨ S = (a + b + c) / 2
Substituting the values , we get :
➨ (3 + 4 + 5) / 2
➨ 12 / 2
➟ S = 6 cm
We got ' s ' now , is 6 cm.
Applying heron's formula :
Area of Triangle = √s(s - a) (s - b) (s - c)
➨ √6(6 - 3) (6 - 4) (6 - 5)
➨ √6 × 3 × 2 × 1
➨ √36
➟ Area = 6 cm²
Therefore,
Area of base is 6 cm²
Now, Using the formula for volume of prism :-
Volume of prism = Area of base × Height of prism
Putting Values in the above formula , we get :-
➨ V = 6 × 10
➟ V = 60 cm³
So,
The volume of prism = 60 cm³ .