Answer:
409[tex]cm^{2}[/tex]
Step-by-step explanation:
The area of the box wuld be c times d which is 15 times 17 which is 255.
the area of the triangle is [tex]\frac{1}{2}\\[/tex] (base x height) = [tex]\frac{1}{2}\\[/tex](28 x 11) = 14 x 11 = 154
154 + 255 = 409. area of 2D shape's unit is squared, so 409 [tex]cm^{2}[/tex]
