Using algebra
3b+5d=34
2b+6d=36
This is a simultaneous equation
Times top equation by two and bottom by 3
6b+10d=68
6b+18d=108
Subtract bottom equation by top one
-8d=-40
d=5
substitute this into an equation
3b+25=34
-25 from both sides
3b=9
b=3
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