Determinants Level 3: 2x2 mixed (+/-5). 2x2 diagonal difference. 1. Diagonal formula1. Diagonal formulaDown diagonal minus up diagonal.determinant equals-3425ad minus bc equals -23down: -3 x 5 = -15up: 4 x 2 = 8-15 - 8 = -23|-3 4; 2 5|: (-3)x5 - 4x2 = -23.
