<h2>
The required positive number is 7.</h2>
Step-by-step explanation:
Let the number = x
To find, the positive number = ?
According to question,

⇒
- 3x - 28 = 0
By Factorisation method,
⇒
- 7x + 4x - 28 = 0
⇒ x(x - 7) + 4(x - 7) = 0
⇒ (x - 7)(x + 4) = 0
⇒ x - 7 = 0 or, x + 4 = 0
⇒ x = 7 or, x = - 4 [ - 4 is a negative number)
⇒ x = 7
Thus, the required positive number is 7.
If we have two similar triangles:
Triangle 1 (base 1 , height1).
Triangle 2 (base 2, height 2)
Then:
base 1 /height 1=base 2 /height 2
Data:
base 1=0.2 m
height 1= 1 m
base 2= 8 m
height 2=x
We calculate the height of the tower:
base 1 /height 1=base 2 /height 2
0.2 m / 1m=8 m / x
x=(8 m * 1 m) / 0.2 m
x=8 m²/0.2 m
x=40 m
Answer. the heigth of the tower will 40 m
3 10 4
9 6 9
6 11 11
12 5 7
8 7 11
the answers are going across