-9 5/6b+2 3/4b+1 5/12b=1 7/27
-9 10/12b+2 9/12b+1 5/12b=34/27
-9 10/12b+4 2/12b=34/27
-5 2/3b=34/27
b=-34/27*3/17
b=-2/9
-9 5/6b+2 3/4b+1 5/12b=1 7/27
-9 10/12b+2 9/12b+1 5/12b=34/27
-9 10/12b+4 2/12b=34/27
-5 2/3b=34/27
b=-34/27*3/17
b=-2/9