Question 15911
Let x=base so area of triangle in this instance is
{{{(x+1)*(x/2)=15}}}
{{{(x^2+x)/2=15}}} multipy both sides by 2
{{{x^2+x=30}}} subtract 30 from both sides to get Quadratic
{{{x^2+x-30=0}}}which factors to
(x-5)(x+6)=0
x-5=0
x=5
x+6=0
x=-6
so obviously your answer is x=5 centimeters(length of base)
Pete