Answer
m$\angle$A=60$^{\circ}$
m$\angle$ABC=120$^{\circ}$
Work Step by Step
If the diagonal is congruent to the sides then it splits the rhombus into two equilateral triangles. Equilateral triangles have 60$^{\circ}$ so m$\angle$A is 60$^{\circ}$. Angle ABC is supplementary to angle A so m$\angle$ABC is 120$^{\circ}$.
