Help pleseee asap

Find the value of the cosine for angle a

Write an equation in slope intercept form of the line passes through the given point and is parallel to the graph of the given equation (0,0); y=3/8 x+2

Tamar is measuring the sides and angles of tuv to determine whether it is congruent to the triangle below. which pair of measurements would eliminate the possibility that the triangles are congruent