how to find the area of all these polygons just given their perimeter, the last one btw says 4 yd, (I will give brainliest answer!!)

11) SQUARE

ar (sq) = s² (s is the side)

and perimeter is 4s

now , perimeter = 4s

28 = 4s

s = 7

now , ar of sq = 49 sq inch

12) dodecagon

perimeter = 12s

48 = 12s ft

s = 4 ft

ar = 3×s²×(2+√3)

ar = 3 × 4² × (2+1.73)

ar = 3×16×3.73

ar = 179.04 sq ft

13) NoNAGON

perimeter = 9s

36 = 9s

s = 4yd

area = 9/4 s²cot(180°/9)

= 98.91 sq yd

14) similar to 11

15)PENTAGON

s = 5 mi

ar =

= 43.01 mi²

16) HEXAGON

perimeter = 6s

18 = 6s

s = 3 cm

ar of hexagon =

= 23.28 cm²

17) Similar to 12)

s = 5mi

ar = 3× 25 × 3.73

ar = 279.75 sq mi

18) OCTAGON

peri meter = 8s

64 = 8s

s = 8 m

ar =

ar = 2(1+1.41)×8²

ar = 2(2.41)×64

= 4.82 × 64

= 308.48 m²

19) SIMILAR TO 15)

s = 4

ar = 27.53

THAT TOOK ME A LOT OF EFFORTS

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step-by-step explanation: