Triangle rst is similar to triangle xyz by the aa similarity postulate. what is the measure of angle x ? triangle one angle r - not given angle s - 28 angle t - not given triangle two angle z- 45 angle y - not given angle x - not given

107 degrees.  By the AA theorem, if 2 corresponding angles in 2 similar triangles have the same measure, then the 3rd in each also have the same measure.  So each triangle have angles of 28, 45, 107. By the triangle angle-sum theorem those have to add up to be 180, and they do!