Question

Height =15cm
Width=2cm
Length=5cm
The total surface area of (TSA) of rectangular prism above can be calculated as follows:
*Area of rectangle in front+area of the surface of the rectangle at the back (they are equal)+
*Area of the surface of the rectangle on the left +area of the surface of the rectangle on the right (they are equal)+
*Area of the surface of the rectangle at the bottom+area of the surface of the rectangular at the top (they are equal)
Given:
The area of the rectangle Infront =15×5=75cm ²


1 determine the area of the rectangle on the left side of the rectangular prism
2 determine the area of the rectangle at the bottom of the rectangular prism
3 determine the total surface area (TSA) of the rectangular prism.

Answer 1

1. ar(rect. on left side of prism) = 30 cm²

2. ar(rect. at bottom of prism) = 10 cm²

3. TSA of prism = 230 cm²

Given:

Height = 15 cm

Width = 2 cm

Length = 5 cm

Dimensions of front side = hl

To find:

1. ar(rect. on left side of prism)

2. ar(rect. at bottom of prism)

3. TSA of prism

Solution:

We are given that,

height h = 15 cm

width w = 2 cm

length l = 5 cm

1. We are given that,

dimensions of front side = hl

⇒ dimensions of left side = wh

⇒ area of left side = 2 cm x 15 cm = 30 cm²

2. It can be inferred that

Dimensions of bottom side = lw

⇒ Area of bottom side = 5 cm x 2 cm = 10 cm²

3. TSA of cuboid = 2(lw + wh + lh)

⇒ TSA = 2(75 + 30 + 10) = 2(115) = 230 cm²

∴ 1. ar(rect. on left side of prism) = 30 cm²

2. ar(rect. at bottom of prism) = 10 cm²

3. TSA of prism = 230 cm²

SPJ2