Elementary Geometry for College Students (5th Edition)

m$\angle$ RSV = 62$^{\circ}$
Using the Segment Addition Postulate, m$\angle$ RST + m$\angle$ TSV = m$\angle$ RSV. Substitute the measures from the problem into the equation. 39 + 23 = m$\angle$ RSV 62 = m$\angle$ RSV