Let the number of pottery articles be ‘x’.
Cost of production of each (in rupees) is = (2x + 3)
∴ 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
If x – 6 = 0, then x = 6
If 2x + 15 = 0, then 2x = -15
∴ x = \(\frac{-15}{2}\)
∴ Number of pottery articles produced is 6.
Cost of production of 6 pottery articles is Rs. 90
Cost of production of 1 pottery article ……….. ?
\(\frac{1\times 90}{6}\) = Rs. 15
OR Cost of Production= 2x + 3
= 2 × 6 + 3
= 12 + 3
= Rs. 15.