Extend the vertical line on the right so it divides the figure into a rectangle and a triangle.
The rectangle is 5 in high and 7 in wide, so has an area of (5 in)*(7 in) = 35 in^2.
The triangle is (5 in -3 in) = 2 in high and (12 in -7 in) = 5 in wide, so has an area of
.. (1/2)*(2 in)*(5 in) = 5 in^2
The total area of rectangle and triangle is 35 in^2 +5 in^2 = 40 in^2.
