1. **State the problem:** Find the vertex, y-intercept, and x-intercepts of the quadratic function $$y = 3x^2 - 12x + 9$$ using calculation.
2. **Vertex formula:** The vertex of a quadratic function $$y = ax^2 + bx + c$$ is at $$x = -\frac{b}{2a}$$.
3. **Calculate the vertex:**
$$a = 3, \quad b = -12, \quad c = 9$$
$$x = -\frac{-12}{2 \times 3} = \frac{12}{6} = 2$$
4. **Find the y-coordinate of the vertex by substituting $$x=2$$ into the function:**
$$y = 3(2)^2 - 12(2) + 9 = 3 \times 4 - 24 + 9 = 12 - 24 + 9 = -3$$
5. **Vertex coordinates:** $$(2, -3)$$
6. **Find the y-intercept:** The y-intercept occurs when $$x=0$$.
$$y = 3(0)^2 - 12(0) + 9 = 9$$
7. **Y-intercept coordinates:** $$(0, 9)$$
8. **Find the x-intercepts:** Set $$y=0$$ and solve for $$x$$:
$$0 = 3x^2 - 12x + 9$$
Divide both sides by 3:
$$0 = \cancel{3}x^2 - \cancel{3}4x + \cancel{3}3 \Rightarrow 0 = x^2 - 4x + 3$$
9. **Factor the quadratic:**
$$x^2 - 4x + 3 = (x - 3)(x - 1)$$
10. **Set each factor to zero:**
$$x - 3 = 0 \Rightarrow x = 3$$
$$x - 1 = 0 \Rightarrow x = 1$$
11. **X-intercept coordinates:** $$(3, 0)$$ and $$(1, 0)$$
**Final answers:**
- Vertex: $$(2, -3)$$
- Y-intercept: $$(0, 9)$$
- X-intercepts: $$(3, 0)$$ and $$(1, 0)$$
Quadratic Points 8F1D82
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