Answer:
21.29 units
Explanation:
30° 60° 90° triangles have a specific side ratio.
With respect to side a, x is side a, x√3 is side b, and 2x is side c.
Therefore the perimeter is the sum of these sides.
c is the long side so:
9 = 2x. x = 9/2 = 4.5.
x√3 = 4.5√3 ≈ 4.5 × 1.73 ≈ 7.79.
Perimeter = x + x√3 + 2x =
(9/2) + (9/2)√3 + 9 = 4.5 + 7.79 + 9 = 21.29.
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Exact answer: (27 + 9√3) / 2
Decimal: 21.29 [Nearest hundredth]