Question 1100427
{{{G=B-6}}}
{{{G*B=135}}}
Substituting,
{{{(B-6)B=135}}}
{{{B^2-6B=135}}}
{{{B^2-6B+9=135+9}}}
{{{(B-3)^2=144}}}
{{{B-3=0 +- 12}}}
Only positive solutions make sense here.
{{{B=3+12}}}
{{{B=15}}}
Use either of the equations to solve for G.