Question 108767
{{{H=B-4}}}
{{{A=16}}}
The formula for the area of a triangle is,
{{{A=(1/2)BH}}}
{{{(1/2)BH=16}}}
{{{(1/2)B(B-4)=16}}}Substitute for H. 
{{{B^2-4B=32}}} Multiply both side by 2, use the Distributive property. 
{{{B^2-4B-32=0}}}Group all terms on one side.
{{{(B-8)(B+4)=0}}} Factor the quadratic equation.
{{{B-8=0}}} Choose the positive root, negative number would not make sense in this application.
{{{B=8}}}
{{{H=B-4}}}
{{{H=4}}}
Check your area.
{{{A=(1/2)BH}}}
{{{A=(1/2)8*4}}}
{{{A=16}}}
Good answer.
B=8 feet, H=4 feet.