Question

A rectangular prism, like the one shown below, has a surface area of 10 square units

Answer 1

The answer is 20 square units

Answer 2

20 square units

Explanations:

The formula for calcuating the surface area of a rectangular prism is expressed as:

`S=2(lw+lh+wh)`

where

l is the length

w is width

h is the height

If the surface area of the prism is 10 square units, hence;

`\begin{gathered} 10=2(lw+wh+lh) \\ lw+wh+lh=5..................\text{ 1} \end{gathered}`

If the length, width and height are doublesd, then;

`\begin{gathered} S=2(2lw+2wh+2lh) \\ S=4(lw+wh+lh)\text{ ..........................2} \end{gathered}`

Substitute equation 1 into 2 to have:

`\begin{gathered} S=4(5) \\ S=20square\text{ units} \end{gathered}`

Therefore the new surface area of the prism will be 20 square units