1. area of a pentagon when 1 side is x is

so if perimiter is 100 then one side is 100/5 or 20
area will be

≈<span>688.2 square yards
2. area of a hexagon when 1 side is length x is

so if permiter is 100 then length of one side is 100/6 or about 16.666666666666
the area will be

≈721.7 square yards
3. area of a regular octagon with side lenghts x is

so if 8 sides then side length of each is 100/8 or 12.5
area will be

≈754.4 square yards
octagon wil have most space
you can tell because the more sides it has, the more it gets to a circle and the more area it encloses with a given perimiter
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The solution is 
<em><u>Solution:</u></em>
Let us assume,

<em><u>Given system of equations are:</u></em>


<em><u>Rewrite the equation using "a" and "b"</u></em>
2a - 3b = -5 ------------ eqn 1
4a + 6b = 14 -------------- eqn 2
<em><u>Let us solve eqn 1 and eqn 2</u></em>
<em><u>Multiply eqn 1 by 2</u></em>
2(2a - 3b = -5)
4a - 6b = -10 ------------- eqn 3
<em><u>Add eqn 2 and eqn 3</u></em>
4a + 6b = 14
4a - 6b = -10
( - ) --------------------
8a = 4

Substitute a = 1/2 in eqn 1

Now let us go back to our assumed values
Substitute a = 1/2 in assumed values

Substitute b = 2 in assumed value

Thus the solution is 
Step-by-step explanation:

Answer:
1. n=
20
/13
2. n=10
3. n=35
4. n=9
That's all I could do, I got tired of typing lol
Step-by-step explanation:
1. 4/n=13/5 we cross multiply, (4)*(5)=13*n, 20=13n Flip the equation. 13n=20, divide 13 on both sides, 13n/13=20/13, n=
20
/13
2. 9/6= 15/n, we cross multiply 9*n=(15)*(6), 9n=90, Divide both sides by 9. 9n/9=90/9 n=10
3. 28/4=n/5 Cross-multiply, (28)*(5)=n*(4), 140=4n Flip the equation.4n=140 Divide both sides by 4. 4n/4=140/4 n=35
4. n/6=6/4 we cross multiply,n*(4)=(6)*(6), 4n=36, Divide both sides by 4 4n/4=36/4. n=9