Question

In the figure below, the two triangular faces of the prism are fight triangles with sides of length 3, 4, and 5. The other three faces are rectangles. What is the surface area of the prism.

72 sq. units 96 sq. units 84 sq. units 108 sq. units

Answer 1

The surface area of the prism will be given by:
SA=(surface area of triangles)+(surface area of rectangles)
surface area of triangles=2(1/2*3*4)=12 sq. units

area rectangles
the length of the hypotenuse will be:
c²=a²+b²
c=√(3²+4²)
c=√25
c=5
area=(3*5)+(4*5)+(5*5)=60

Total area=60+12=72 sq. units

Answer: 72 sq. units