for keys in matrix_1:
for key, values in zip(keys, matrix_2):
print([(key, value, key*value) for value in values])
[(2, 8, 16), (2, 9, 18)]
[(3, 4, 12), (3, 5, 15)]
[(4, 3, 12), (4, 6, 24)]
[(5, 8, 40), (5, 9, 45)]
[(6, 4, 24), (6, 5, 30)]
[(7, 3, 21), (7, 6, 42)]