Answer: The required width of the rectangle is 7 cm.
Step-by-step explanation: Given that a rectangle has perimeter 84 cm and length 35 cm.
We are to find the width of the rectangle.
Let w represents the width of the rectangle.
According to the given information,
length, l = 35 cm and perimeter, P = 84 cm.
Therefore, we get
[tex]P=2(l+b)\\\\\Rightarrow 84=2(35+w)\\\\\Rightarrow 42=35+w\\\\\Rightarrow w=42-35\\\\\Rightarrow w=7.[/tex]
Thus, the required width of the rectangle is 7 cm.
