1. **State the problem:** We need to find the cost equation $C(x)$ for producing $x$ items, given a cost per item of 9 and fixed costs of 1950. 2. **Formula used:** The linear cost model is given by: $$C(x) = ext{fixed cost} + ( ext{cost per item}) \times x$$ 3. **Apply the values:** Substitute fixed cost = 1950 and cost per item = 9: $$C(x) = 1950 + 9x$$ 4. **Interpretation:** This means the total cost $C(x)$ increases by 9 for each additional item produced, starting from a base cost of 1950. 5. **Final answer:** $$C(x) = 1950 + 9x$$