maebr  20.250000 * 3.000000 + 10.500000  -> 71.250000
madbr  42.750000 * -2.000000 + -10.500000  -> -96.000000
msebr  20.250000 * 3.000000 - 10.500000  -> 50.250000
msdbr  42.750000 * -2.000000 - -10.500000  -> -75.000000