<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.