6.5 in. 5 in 7.5 in. What is the total surface area of this prism in square inches?
we have that
the total surface area of a prism is equal to
SA=2B+Ph
where
B is the area of the base
P is the perimeter of the base
h is the height of the prism
Let
L=6.5 in
W=5 in
H=7.5 in
so
B=L*W=(6.5*5)=32.5 in2
P=2(L+W)=2(6.5+5)=23 in
H=7.5 in
therefore
SA=2(32.5)+23(7.5)
SA=237.5 in2
surface area is 237.5 square inches
see the attached figure to better understand the problem
the surface area is the area of its six rectangular faces
so
SA=2(6.5)8(5)+2((5)(7.5)+2(6.5)*(7.5)=237.5 in2