1. **State the problem:** Find the roots and vertex of the quadratic function $$y = x^2 + 14x - 72$$.
2. **Formula for roots:** Use the quadratic formula $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ where $$a=1$$, $$b=14$$, and $$c=-72$$.
3. **Calculate the discriminant:** $$\Delta = b^2 - 4ac = 14^2 - 4(1)(-72) = 196 + 288 = 484$$.
4. **Find the roots:**
$$x = \frac{-14 \pm \sqrt{484}}{2(1)} = \frac{-14 \pm 22}{2}$$
5. **Calculate each root:**
- $$x_1 = \frac{-14 + 22}{2} = \frac{8}{2} = 4$$
- $$x_2 = \frac{-14 - 22}{2} = \frac{-36}{2} = -18$$
6. **Formula for vertex:** The vertex $$x$$-coordinate is $$x = -\frac{b}{2a} = -\frac{14}{2} = -7$$.
7. **Find the vertex $$y$$-coordinate:** Substitute $$x = -7$$ into the equation:
$$y = (-7)^2 + 14(-7) - 72 = 49 - 98 - 72 = -121$$.
8. **Final answers:**
- Roots: $$4$$ and $$-18$$
- Vertex: $$(-7, -121)$$
Roots Vertex 4153E7
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