It is convenient to draw the triangles, as follow:
Take into account that if angles X and A are right angles, then, they are congruent. Moreover, angles B and Z are congruent.
Due to two pair of angles are congruent, it is necessary that the third pairs of angles Y and C are congruent too.
Hence, due to all angles of triangle ABC are congruents with angles of triangle XYZ, you can conclude that both traingles are SIMILAR.
