Question

Please help me with the question below (also please explain).

Answer 1

It is a composite solid, the surface area wil be given by the surface area of the rectangular prism and the surface area of the triangular prism, therefore:

The surface area of the rectangular prism is:

`SA_(rectangular)=2(12\cdot3+4\cdot3+12\cdot(4)/(2))=2(72)=144cm^2`
`SA_(triangular)=5\cdot12+5\cdot4+13\cdot4=132cm^2`

Therefore, the surface area of the composite figure is:

`SA=144cm^2+132cm^2=276cm^2`

Answer:

276 cm²