Question 146941
The area of a triangle is 
{{{A=bh/2}}}
Let’s substitute for the known values,
{{{x^2+5x+6=b(x+3)/2}}}
We can recognize that the area can be simplified into its factors.
{{{x^2+5x+6=(x+2)(x+3)}}}
We can again substitute,
{{{(x+2)(x+3)=b(x+3)/2}}}
{{{(x+2)cross((x+3))=b*cross((x+3))/2}}}
{{{b=2(x+2)}}}