1. **Problem:** Expand and simplify the expression $y = (x - 1)(x + 3)$. Find the standard quadratic form. 2. **Formula:** Use the distributive property (FOIL method) to expand: $$ (a + b)(c + d) = ac + ad + bc + bd $$ 3. **Step-by-step solution:** - Multiply the first terms: $x \times x = x^2$ - Multiply the outer terms: $x \times 3 = 3x$ - Multiply the inner terms: $-1 \times x = -x$ - Multiply the last terms: $-1 \times 3 = -3$ 4. **Combine like terms:** $$ x^2 + 3x - x - 3 = x^2 + (3x - x) - 3 = x^2 + 2x - 3 $$ 5. **Final answer:** $$ y = x^2 + 2x - 3 $$ This is the quadratic function in standard form.