Answer:
48 meters.
Explanation:
The perimeter of a parallelogram is given by the formula:
![P=2(a+b)](https://img.qammunity.org/2021/formulas/mathematics/high-school/qwe13sz6uv9ow9uip5ehi0mybzsgkbqy68.png)
Where a is the measure of the length (top), and b is the measure of the slant height (side).
We know that the perimeter is 102.
We also know that the top is 3.
So, let’s substitute 102 for P and 3 for a and solve for b, the side. So:
![102=2(3+b)](https://img.qammunity.org/2021/formulas/mathematics/high-school/bhyarjoq3q2v4usf69hq7650sdm33rtq3r.png)
Divide both sides by 2:
![51=3+b](https://img.qammunity.org/2021/formulas/mathematics/high-school/ey53txpmy8bvjqd728vas1cqs9uhsh4qfz.png)
Subtract 3 from both sides:
![b=48\text{ meters}](https://img.qammunity.org/2021/formulas/mathematics/high-school/sd1k2a3ljzdo92hqwpa2d034j0xbe0se3m.png)
Therefore, the side measures 48 meters.