Missing sideArea given
Name: Date:
Find the missing side. All lengths are in centimeters.
1 cm
2 cm
3 cm
4 cm
5 cm
6 cm
7 cm
8 cm
Find a side from the area worksheets
If a rectangle covers 48 square centimeters and one side is 6, the other has to be 8 — because 6 times 8 is 48. These free printable worksheets run the area formula backward, every figure marked with A, so the move is always to divide.
If they get stuck
Find a side from the area
The answer key prints on a separate page.
What's on this sheet
The mixed missing-side sheets switch between area and perimeter, so a child has to read the figure and choose a method. This one is area throughout: the rectangle shows A and one side, and the missing side is the area divided by the side you were given. One operation, repeated, is what makes the reverse reading of the formula stick before it is mixed with anything else.
Why this sheet works
Every rectangle is built from two whole sides, so the area divides evenly and the answer is always a whole number — never 7.5. The figure carries the letter A with the number so a child reads area rather than guessing, which is also their first meeting with a formula being used in reverse.
How this one works
One question from a sheet like this one, worked a step at a time — with a sentence saying what just happened and why.
Find a side from the area, step by step