Question

The 3rd grade classroom has a perimeter of 130 feet. if it is 25 feet wide, how many feet long is the classroom

Answer 1

Let W be the wide and L the length of the classroom, then we can write

`2* W+2* L=130`

Since W=25 feets, we get

`\begin{gathered} 2*25+2* L=130 \\ 50+2* L=130 \end{gathered}`

If we move 50 to the right hand side as -50, we obtain

`2* L=130-50`

since 130-50=80, we get

`2* L=80`

Now, if we move the coefficient 2 to the right hand side, we obtain

`\begin{gathered} L=(80)/(2) \\ L=40 \end{gathered}`

that is, the lenght of the classroom is equal to 40 feets.