Let ∠A, ∠B, and ∠C be acute angles. Use a calculator to approximate the measures of ∠A, ∠B, and ∠C to the nearest tenth of a degree.

cos A = 0.31, sin B = 0.89, tan C = 0.52

1. ∠A = 71.9°

2. ∠B = 62.9°

3. ∠C = 27.5°

Step-by-step explanation:

By using a calculator, we have;

cos A = 0.31

sin B = 0.89

tan C = 0.52

1. Therefore, ∠A = cos⁻¹ (0.31), inputting the digits in the calculator and looking for the inverse sign, we have;

∠A = cos⁻¹ (0.31) = 71.94° = 71.9° to the nearest tenth of a degree.

2. For sin B = 0.89, we have;

∠B = sin⁻¹0.89 = 62.873° ≈ 62.9° with the answer rounded to the nearest tenth of a degree.

3. Similarly, for tan C = 0.52, inputting the values in the calculator and pressing the tan⁻¹ button, we have;

∠C = tan⁻¹ (0.52) = 27.474°, which is 27.5° rounded to the nearest tenth of a degree.