Answer:

Step-by-step explanation:
we know that
Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.
so

where
a, b and c are the length sides of triangle
s is the semi-perimeter of triangle
we have

Find the semi-perimeter s

Find the area of triangle



Simplify

Answer:
C
Step-by-step explanation:
If x is the average (arithmetic mean) of m and 9, y is the average of 2m and 15, and z is the average of 3m and 18,
x=(m+9)/2
y=(2m+15)/2
z=(3m+18)/2
the average of x, y, and z
=(x+y+z)/3
=(m+9+2m+15+3m+18)/3
=(6m+42)/3
=2m+14
ans is C
Top:
x / (x + 1) - 1 / x
= [x^2 - (x +1)] / x(x+1)
= (x^2 - x - 1 ) / x (x+1)
Bottom:
x / (x + 1) + 1 / x
= [x^2 + (x +1)] / x(x+1)
= (x^2 + x + 1 ) / x (x+1)
Now you have:
(x^2 - x - 1 ) / x (x+1)
----------------------------
(x^2 + x + 1 ) / x (x+1)
= (x^2 - x - 1 ) / x (x+1) * x (x+1) / (x^2 + x + 1 )
= (x^2 - x - 1 ) /(x^2 + x + 1 )
Answer:
x^2 - x - 1
---------------------
x^2 + x + 1
We divide the total sum of the angles by 20

=18 sides
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Present the numbers in decimal
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0.25 = 0.25
3/8 = 0.375
5/16 = 0.3125
<span><em>(It is easier to arrange the number using decimals)</em>
</span>
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Arrange the numbers
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0.25 (0.25) , 0.3125 (5/16) , 0.0375 (3/8)
<em>(Put the original numbers given in your final answer)</em>
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Answer: 0.25 , 5/16 , 3/8
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