Question

Need help on this volume/surface area

Answer 1

8. Answer:

Imagine opening the Triangular prism

We will have 2 triangles at the base

and 3 rectangles

The sides of the triangle : base 9in, height 3in

Area of Triangle

=
`(1)/(2) * base * height = (1)/(2) * 9*3 =(27)/(2)`

Now the rectangles

Rectangle1 with sides 9in and 15in, Area = 9*15 = 135

Rectangle 2 with sides 5in and 15in , Area = 5*15 = 75

Rectangle 3 with sides 6in and 15in, Area = 6*15 = 90

Now the total area of the prism

=
`(27)/(2)+(27)/(2)+135+75+90 = 27+ 135+75+ 90 = 327in^(2)`