## Elementary Geometry for College Students (6th Edition)

m$\angle$3=110$^{\circ}$
Angles 13 and 15 are corresponding angles so they are congruent. m$\angle$13=m$\angle$15=70$^{\circ}$ Angles 15 and 3 are same side exterior angles so they are supplementary. m$\angle$15+m$\angle$3=180 70+m$\angle$3=180 m$\angle$3=110$^{\circ}$