1. **State the problem:** Solve the system of equations:
$$y = x^2 - 7x - 5$$
$$y = -x^2 - 3x + 11$$
We want to find the values of $x$ and $y$ where these two parabolas intersect.
2. **Set the equations equal to each other:** Since both equal $y$, set the right sides equal:
$$x^2 - 7x - 5 = -x^2 - 3x + 11$$
3. **Bring all terms to one side:**
$$x^2 - 7x - 5 + x^2 + 3x - 11 = 0$$
Simplify:
$$2x^2 - 4x - 16 = 0$$
4. **Simplify the equation by dividing all terms by 2:**
$$\cancel{2}x^2 - \cancel{2} \cdot 2x - \cancel{2} \cdot 8 = 0 \implies x^2 - 2x - 8 = 0$$
5. **Factor the quadratic:**
$$x^2 - 2x - 8 = (x - 4)(x + 2) = 0$$
6. **Solve for $x$:**
$$x - 4 = 0 \implies x = 4$$
$$x + 2 = 0 \implies x = -2$$
7. **Find corresponding $y$ values by substituting back into one of the original equations, e.g., $y = x^2 - 7x - 5$:**
For $x=4$:
$$y = 4^2 - 7 \cdot 4 - 5 = 16 - 28 - 5 = -17$$
For $x=-2$:
$$y = (-2)^2 - 7 \cdot (-2) - 5 = 4 + 14 - 5 = 13$$
8. **Write the solution as ordered pairs:**
$$(4, -17), (-2, 13)$$
**Final answer:** The solutions to the system are $(4, -17)$ and $(-2, 13)$.
Solve System 300753
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