Question 317098
# 1

{{{(9b+5)(4b-12)=0}}} Start with the given equation


Now set each factor equal to zero:


{{{9b+5=0}}} or  {{{4b-12=0}}} 


Now solve for b for each factor:


{{{b=-5/9}}} or  {{{b=3}}} 


So the solutions are {{{b=-5/9}}} or  {{{b=3}}} 


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# 2

{{{b^2+8b+12=0}}} Start with the given equation



{{{(b+6)(b+2)=0}}} Factor the left side 



Now set each factor equal to zero:

{{{b+6=0}}} or  {{{b+2=0}}} 


{{{b=-6}}} or  {{{b=-2}}}    Now solve for b in each case



So the solutions are {{{b=-6}}} or  {{{b=-2}}}