Answer:
base 5 inches and height 2 inches
Explanation:
Area of triangle =

Using this formula and the info on base=2x and height = x-3,
we obtain:

Solve the quadratic equation:

Therefore there are two solutions to this equation:
One when x=5 and the other when x=-2
This last option has no physical meaning because the base (or for the matter any side of a triangle) cannot be a negative number.
Therefore x=5
That means that the base (which is 2 times x) must be 2 times 5 = 10 inches,
and the height (which is x-3) must be 5 minus 3 that gives 2 inches