Chapter 7 - Applications of Trigonometry and Vectors - Section 7.2 The Ambiguous Case of the Law of Sines - 7.2 Exercises - Page 310: 17

We can not construct a triangle with the values given in this question.

We can use the law of sines to find the angle $A$: $\frac{b}{sin~B} = \frac{a}{sin~A}$ $sin~A = \frac{a~sin~B}{b}$ $sin~A = \frac{(859~m)~sin~(74.3^{\circ})}{783~m}$ $sin~A = 1.056$ Since there is no angle A such that $sin~A \gt 1$, the angle A is not defined. We can not construct a triangle with the values given in this question.