Chapter 7 - Applications of Trigonometric Functions - Section 7.3 The Law of Cosines - 7.3 Assess Your Understanding - Page 559: 35

$A \approx40.8^\circ$ $B \approx60.6^\circ$ $C\approx 78.6^\circ$

1. Use the Law of Cosines, we have $A=cos^{-1}(\frac{(8)^2+(9)^2-(6)^2}{2(8)(9)})\approx40.8^\circ$ 2. Use the Law of Cosines, we have $B=cos^{-1}(\frac{(6)^2+(9)^2-(8)^2}{2(6)(9)})\approx60.6^\circ$ 3. We have $C\approx(180-40.8-60.6)=78.6^\circ$