Answer:
45
Step-by-step explanation:
Since the values are relatively small substitute i = 1 to 5 into 3i and sum
(3 × 1) + (3 × 2) + (3 × 3) + (3 × 4) + (3 × 5)
= 3 + 6 + 9 + 12 + 15
= 45
Answer:
The quadratic equation is x^2 -12x -120 = 0
where x represents the length of the field
Step-by-step 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