446,322 views
20 votes
20 votes
The length of a rectangular picture frame is 28 inches and its perimeter is 84 inches. What is the width of the picture frame? *

User Simple Lime
by
2.5k points

1 Answer

24 votes
24 votes

The perimeter of a rectangle can be calculated using the following formula:


P=2w+2l

Where

"w" represents the width of the rectangle

"l" represents the length of the rectangle

If you know the perimeter and length of a rectangle, you can use the formula to determine the width. The first step is to write the formula for the width:

-Pass 2l to the left side of the expression by applying the opposite operation to both sides of it:


P-2l=2w

-Divide both sides by 2


\begin{gathered} (P-2l)/(2)=(2w)/(2) \\ (P-2l)/(2)=w \end{gathered}

Now that we have determined a formula for w, replace the value of the length and perimeter and calculate the width:

P=84in

l=28in


\begin{gathered} w=(84-2\cdot28)/(2) \\ w=(84-56)/(2) \\ w=(28)/(2) \\ w=14 \end{gathered}

The width of the rectangular frame is 14 inches long

User Yan Q
by
3.0k points