Answer:
<em>5 meters must be added to both the length and the width</em>
Step-by-step explanation:
<u>Area of a Rectangle</u>
A rectangle of width W and length L has an area calculated as:
A = W*L
Initially, the lot has a width of W1=25 m and a length of L1 = 120 m, thus its area is:

When adding x meters to the width and the length, the new area is:

Operating:

We now calculate the increased area by subtracting A2-A1:


We are given this area is 750 square meters, thus:

Rearranging:

Factoring:

Solving:
x=5, x=-150
Taking the positive solution x=5:
5 meters must be added to both the length and the width