Question

If A= ("-2" 6 1) (1 9 "-6)" ("-9" 9 "-9)" and B= ("-5" 9 6) (-2 "-7" 4) (1 10 "-1)," find "-4A" + 6B

Answer 1

40 + 6(-7 + 20) = 6
40 - 42 + 12a = 6
16a = 48
a =3