The perimeter of equilateral triangle is 21m. Find the area. Using Heron's Formula
1 answer:
Answer:
A ≈ 21.22 m²
Step-by-step explanation:
The area (A) of a triangle using Heron's formula is
A =
where s is the semi perimeter and a, b, c the sides of the triangle.
Here the perimeter of the equilateral triangle is 21 m , then
a = b = c = 21 ÷ 3 = 7 m
s = 21 ÷ 2 = 10.5
Then
A =
=
=
≈ 21.22 m² ( to 2 dec. places )
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(1/3) × the cone's volume = The cylinder's volume.
Step-by-step explanation:
Step 1:
The volume of any cone is obtained by multiplying with π, the square of the radius (
) and the height (
).
So the volume of the cone, .
Step 2:
The cylinder's volume is nearly the same as the cone but instead by multiplying we multiply with 1.
So the cylinder's volume is determined by multiplying π with the square of the radius of the cylinder () and the height of the cylinder (
).
So the the cone's volume, .
Step 3:
Now we equate both the volumes to each other.
The cone's volume : The cylinder's volume = =
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So if we multiply the cone's volume with we will get the cylinder's volume with the same dimensions.