Chapter 13, Trigonometric Ratios and Functions - 13.6 Apply the Law of Cosines - 13.6 Exercises - Skill Practice - Page 892: 30

$$A=720\sqrt{2}$$

By Heron's Formula, we know: $$A=\sqrt{s(s-a)(s-b)(s-c)}$$ Where: $$s=\frac{a+b+c}{2}$$ Thus, we find: $$s=\frac{43+59+48}{2}=75 \\ A=\sqrt{75\left(75-43\right)\left(75-59\right)\left(75-48\right)} \\ A=720\sqrt{2}$$