Which formula should be used to find the area of the composite shape?

The last option seems the best one: the figure is composed of a square/rectangle and a triangle. The area of the rectangle is the product of its dimension (i.e. [tex]lw[/tex]), while the area of the triangle is half the product of the base and height ([tex]\frac{1}{2}bh[/tex]).
The sum of the two areas is the area of the composite shape.
ANSWER
area equals half of base times height plus length times width so d