Quadratic Completing Square
1. **Problem statement:** Solve the quadratic equation $x^2 + 6x + 5 = 0$ by completing the square.
2. **Step 1: Move constant to the other side.**
$$x^2 + 6x = -5$$
3. **Step 2: Complete the square.**
Take half the coefficient of $x$, which is $6$, half is $3$, then square it, $3^2 = 9$.
Add $9$ to both sides:
$$x^2 + 6x + 9 = -5 + 9$$
$$ (x + 3)^2 = 4 $$
4. **Step 3: Take square roots of both sides.**
$$ x + 3 = \pm 2 $$
5. **Step 4: Solve for $x$.**
$$ x = -3 \pm 2 $$
6. **Step 5: Find the two solutions.**
$$ x_1 = -3 + 2 = -1 $$
$$ x_2 = -3 - 2 = -5 $$
**Final answer:** The solutions are $x = -1$ and $x = -5$.
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1. **Problem statement:** Solve the quadratic equation $2x^2 + 8x - 10 = 0$ by completing the square.
2. **Step 1: Divide all terms by the coefficient of $x^2$ (which is 2).**
$$ x^2 + 4x - 5 = 0 $$
3. **Step 2: Move constant term to the other side.**
$$ x^2 + 4x = 5 $$
4. **Step 3: Complete the square.**
Take half of $4$ is $2$, square it: $2^2 = 4$.
Add $4$ to both sides:
$$ x^2 + 4x + 4 = 5 + 4 $$
$$ (x + 2)^2 = 9 $$
5. **Step 4: Take square roots.**
$$ x + 2 = \pm 3 $$
6. **Step 5: Solve for $x$.**
$$ x = -2 \pm 3 $$
7. **Step 6: Find the two solutions.**
$$ x_1 = -2 + 3 = 1 $$
$$ x_2 = -2 - 3 = -5 $$
**Final answer:** The solutions are $x = 1$ and $x = -5$.