Answer:

Explanation:
The figure can be decomposed in an equilateral triangle, with sides = 3'', and a rectangle with sides 3'' and 6''.
The area of an equilateral triangle (A1) is calculated as follows:

where a refers to the length of each side of the triangle. Here a = 3. Replacing:


The area of the rectangle is: 3*6 = 18'' = A2
The total area (T.A) is the addition of A1 to A2, So:

Notice that the line after after the + sign is not a subtract symbol, it is the line between numerator and denominator of the answer