5+[16-(9:a x 8+7)] x 6= 4 :(1 x 2) + 3 x 3
5+[16-(9:a x 8+7)] x 6= 4 : 2 + 9
5+[16-(9:a x 8+7)] x 6= 2 + 9
5+[16-(9:a x 8+7)] x 6= 11
[16-(9:a x 8+7)] x 6 = 11 - 5
[16-(9:a x 8+7)] x 6 = 6
16-(9:a x 8+7) = 6 : 6
16-(9:a x 8+7) = 1
9:a x 8+7 = 16 - 1
9:a x 8+7 = 15
9:a x 8 = 15 - 7
9:a x 8 = 8
9:a = 8 : 8
9:a = 1
a = 9 : 1
a = 9
