The height of a triangle is 8 inches more than its base. the area of the triangle is 104.5 square inches. find the base and height.

Let
b------> the base of the triangle
h------> the height of the triangle

we know that
area of the triangle=b*h/2
h=b+8-----> equation 1
area=104.5 in²
104.5=b*h/2-----> 209=b*h-----> equation 2

substitute equation 1 in equation 2
209=b*[b+8]----> 209=b²+8b-----> b²+8b-209=0

using a graph tool---> to resolve the second order equation
see the attache figure

the solution is 
b=11 in
h=b+8----> h=19 in

the answer is
the base is 11 in and the height is 19 in

Iwould say always for the both of them