Max Min Quadratic 83D268
1. **State the problem:** We need to find the maximum or minimum value of the quadratic function $$y = -10x^2 + 20x - 5$$.
2. **Recall the formula:** For a quadratic function $$y = ax^2 + bx + c$$, the vertex (which gives the maximum or minimum) is at $$x = -\frac{b}{2a}$$.
3. **Identify coefficients:** Here, $$a = -10$$, $$b = 20$$, and $$c = -5$$.
4. **Calculate the vertex x-coordinate:**
$$x = -\frac{20}{2 \times (-10)} = -\frac{20}{-20} = 1$$.
5. **Calculate the vertex y-coordinate by substituting $$x=1$$ into the function:**
$$y = -10(1)^2 + 20(1) - 5 = -10 + 20 - 5 = 5$$.
6. **Determine if it is a maximum or minimum:** Since $$a = -10 < 0$$, the parabola opens downward, so the vertex is a maximum point.
7. **Final answer:** The maximum value of $$y$$ is $$5$$ at $$x = 1$$, so the vertex is $$(1, 5)$$.
**Answer:** (1, 5)