Answer:
c = 2√3 ≈ 3.464
Step-by-step explanation:
A 30°-60°-90° triangle is a "special" triangle that has sides in the ratios ...
1 : √3 : 2 . . . . . shortest to longest.
Comparing those to the side measures you have, we see ...
1 : √3 : 2 = b : 3 : c
Multiplying the basic ratios by √3 gives a value that matches the long side:
√3 : 3 : 2√3 = b : 3 : c
Then the value of c is 2√3 ≈ 3.464.
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Additional comment
Side length b is √3 ≈ 1.732.
