Answer:
The quadratic equation is x^2 -12x -120 = 0
where x represents the length of the field
Explanation:
We want to make an expression in terms of a quadratic equation;
Let the length of the field be x mm , then the width will be (x-12) mm
Mathematically , the area of the field will be L * B
Thus;
x * (x-12) = 120
That gives;
x^2 -12x = 120
x^2 -12x -120 = 0