Using the law of the sine we have: (sine (34) / 42) = (sine (x) / 61) From here, we clear the value of x. We have then: sine (x) = (61/42) * (sine (34)) We apply the inverse to both sides: Arcosine (sine (x)) = Arcosine ((61/42) * (sine (34))) We get then: x = Arcosine ((61/42) * (sine (34))) x = 54.3 degrees Answer: m∠X = 54.3
