Question 363774
I will assume that the problem is as follows:
a trapezoid has an area of {{{185d^2}}} sq. meters and a height of 15d meters. The lower base is 10d meters more than the upper base. Find the length of the upper base.

Then the solution is as follows:  {{{185d^2 = (15d/2)(u + u+10)}}}, where u is the length of the upper base.  Then
{{{74d/3 = 2u + 10d}}}, after simplification.
{{{74d/3 - 10d = 2u}}},
{{{44d/3 = 2u}}},
{{{u = 22d/3}}} meters, the length of the upper base.