Solution: Let the number of articles produced in a day = x
∴ Cost of production of each article = Z (2x + 3)
According to the condition,
Total cost = 90
⇒ x × (2x + 3) = 90
⇒ 2x2 + 3x = 90
⇒ 2x2 + 3x – 90 = 0
⇒ 2x2 – 12x + 15x – 90 = 0
⇒ 2x(x – 6) + 15(x – 6) = 0
⇒ (x – 6) (2x+15) = 0
⇒ x – 6 = 0 ⇒ x = 6
![image](https://www.sarthaks.com/?qa=blob&qa_blobid=5980925651339920744)
But the number of articles cannot be negative.
![image](https://www.sarthaks.com/?qa=blob&qa_blobid=13513086065394511907)
⇒ x = 6
∴ Cost of each article = Rs (2 × 6 + 3) = Rs. 15
Thus, the required number of articles produced is 6 and the cost of each article is Rs. 15.