What is equal to the product HJ?
You must multiply each element of first row of H and first column of J to get a11 = 47 + -23 + 58 = 28 - 6 + 40 = 62 You now multiply each element of second row of H and first column of J to get a21 = 67 + 13 + -38 = 42 + 3 - 24 = 21