In δabc, if a = c = 16 centimeters and m∠b = 85°, what is b to two decimal places? . 16.56 centimeters. . 21.62 centimeters. . 24.48 centimeters. . 28.86 centimeters.

Since we are to find B and given only the lengths of the adjacent sides and the opposite angles, use Law of Cosines to answer the question above. This law is expressed as follows,
                                     b² = a² + c² - 2ac x (cos B)
Substituting,
                                 b² = 16² + 16² - 2(16)(16) x (cos 85°)
The value of b is approximately equal to 21.62 cm. 

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