To find the perimeter of a rectangle, you need to add all of the side lengths together.
We are given that the width of one side is 46 cm. We also know that the perimeter is 208 cm.
2 sides of the rectangle will be 46 cm and the other 2 will be x (we don't know these as of now, replace it with x)
46+46=92
This is your equation to solve:
92+2x=208
You're trying to get x by itself, so you need to subtract 92 from each side.
This will be your equation after subtracting 92:
2x=116
Now, all you need to do is divide by 2 on each side to get x by itself.
x=58
This means that the rectangle's length is 58 cm.
To check this, add all of your side lengths together:
46+46+58+58=208
If you have any questions, don't hesitate to ask!