Can you please help answer this

Triangle abc has side lengths: ab = 3.5  cm, bc = 2.4 cm, and ac = 4.2 cmδabc ≅ δhjkwhat is the length of side hj?

Quadrilateral ghij has coordinates g(5, 1), h(4, -3), i(6, -1), and j(2, 1). if the quadrilateral is reflected over the line y = x, what are the coordinates of h'?

Marking brainliest for original answer.. are these two triangles similar? how can you tell?