We want to check whether the side length of the given figure is proportional to its . Let's start by finding the area of the figure for the side length of 1, 2, 3, and 4 units. Let's use another table to organize our information.
| Side Length (units)
|
1
|
2
|
3
|
4
|
| Area (square units)
|
|
|
|
|
Recall that the equals its side length .
| Side Length (units)
|
1
|
2
|
3
|
4
|
| Area (square units)
|
1^2=1
|
2^2=4
|
3^2=9
|
4^2=16
|
For each side length, we can write the relationship of the area and side length as a ratio in simplest form.
| Side Length (units)
|
1
|
2
|
3
|
4
|
| Area (square units)
|
1
|
4
|
9
|
16
|
| Ratio
|
1/1=1
|
2/4=1/2
|
3/9=1/3
|
4/16=1/4
|
Two quantities are proportional if they have a constant ratio or unit rate. For relationships in which this ratio is not constant, the two quantities are not proportional. In this case, the ratios are not the same, so the area of the square is not proportional to its side length.