Answer:
D.) 11.8 cm
Step-by-step explanation:
The short side has length ...
5·sin(30°) = 2.5
The long side has length ...
5·cos(30°) ≈ 4.33
The sum of all side lengths is ...
5 + 2.5 + 4.33 = 11.83 . . . . cm
The perimeter is about 11.8 cm.
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The mnemonic SOH CAH TOA can help you remember the relationship between trig functions and side lengths:
Sin = Opposite/Hypotenuse ⇒ Opposite = Hypotenuse × Sin
Cos = Adjacent/Hypotenuse ⇒ Adjacent = Hypotenuse × Cos
