1. **Problem:** Solve the quadratic equation $-3x^2 - 27 = 0$.
2. **Step 1:** Add 27 to both sides:
$$-3x^2 - 27 + 27 = 0 + 27 \implies -3x^2 = 27$$
3. **Step 2:** Divide both sides by $-3$:
$$\cancel{-3}x^2 = \frac{27}{\cancel{-3}} \implies x^2 = -9$$
4. **Step 3:** Take the square root of both sides:
$$x = \pm \sqrt{-9} = \pm 3i$$
5. **Answer:** $x = \pm 3i$ (complex roots).
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1. **Problem:** Solve $x^2 + 4x + 5 = 0$.
2. **Step 1:** Use quadratic formula $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ with $a=1$, $b=4$, $c=5$.
3. **Step 2:** Calculate discriminant:
$$b^2 - 4ac = 4^2 - 4(1)(5) = 16 - 20 = -4$$
4. **Step 3:** Substitute into formula:
$$x = \frac{-4 \pm \sqrt{-4}}{2} = \frac{-4 \pm 2i}{2}$$
5. **Step 4:** Simplify:
$$x = -2 \pm i$$
6. **Answer:** $x = -2 \pm i$ (complex roots).
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1. **Problem:** Solve $5x^2 - 14x - 3 = 0$.
2. **Step 1:** Use quadratic formula with $a=5$, $b=-14$, $c=-3$.
3. **Step 2:** Calculate discriminant:
$$(-14)^2 - 4(5)(-3) = 196 + 60 = 256$$
4. **Step 3:** Substitute:
$$x = \frac{14 \pm \sqrt{256}}{2 \times 5} = \frac{14 \pm 16}{10}$$
5. **Step 4:** Calculate roots:
$$x_1 = \frac{14 + 16}{10} = \frac{30}{10} = 3$$
$$x_2 = \frac{14 - 16}{10} = \frac{-2}{10} = -\frac{1}{5}$$
6. **Answer:** $x = 3$ or $x = -\frac{1}{5}$.
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1. **Problem:** Solve $3x^2 - 22x + 7 = 0$.
2. **Step 1:** Use quadratic formula with $a=3$, $b=-22$, $c=7$.
3. **Step 2:** Calculate discriminant:
$$(-22)^2 - 4(3)(7) = 484 - 84 = 400$$
4. **Step 3:** Substitute:
$$x = \frac{22 \pm \sqrt{400}}{2 \times 3} = \frac{22 \pm 20}{6}$$
5. **Step 4:** Calculate roots:
$$x_1 = \frac{22 + 20}{6} = \frac{42}{6} = 7$$
$$x_2 = \frac{22 - 20}{6} = \frac{2}{6} = \frac{1}{3}$$
6. **Answer:** $x = 7$ or $x = \frac{1}{3}$.
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1. **Problem:** Solve $\log_2(x + 2) + \log_2(x) = 3$.
2. **Step 1:** Use log property: $\log_b A + \log_b B = \log_b (AB)$.
3. **Step 2:** Combine logs:
$$\log_2(x(x+2)) = 3$$
4. **Step 3:** Convert to exponential form:
$$2^3 = x(x+2)$$
$$8 = x^2 + 2x$$
5. **Step 4:** Rearrange:
$$x^2 + 2x - 8 = 0$$
6. **Step 5:** Factor:
$$(x + 4)(x - 2) = 0$$
7. **Step 6:** Solve:
$$x = -4 \text{ or } x = 2$$
8. **Step 7:** Check domain (arguments of logs must be positive):
$$x > 0, x+2 > 0$$
9. **Step 8:** $x = -4$ invalid, $x = 2$ valid.
10. **Answer:** $x = 2$.
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1. **Problem:** Solve $\log_8 x + \log_8 (x + 6) = \log_8 (5x + 12)$.
2. **Step 1:** Use log property:
$$\log_8 (x(x+6)) = \log_8 (5x + 12)$$
3. **Step 2:** Equate arguments:
$$x(x+6) = 5x + 12$$
4. **Step 3:** Expand and rearrange:
$$x^2 + 6x - 5x - 12 = 0$$
$$x^2 + x - 12 = 0$$
5. **Step 4:** Factor:
$$(x + 4)(x - 3) = 0$$
6. **Step 5:** Solve:
$$x = -4 \text{ or } x = 3$$
7. **Step 6:** Check domain:
$$x > 0, x+6 > 0$$
8. **Step 7:** $x = -4$ invalid, $x = 3$ valid.
9. **Answer:** $x = 3$.
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1. **Problem:** Solve $2x^2 + 7x + 3 = 0$.
2. **Step 1:** Use quadratic formula with $a=2$, $b=7$, $c=3$.
3. **Step 2:** Calculate discriminant:
$$7^2 - 4(2)(3) = 49 - 24 = 25$$
4. **Step 3:** Substitute:
$$x = \frac{-7 \pm 5}{2 \times 2} = \frac{-7 \pm 5}{4}$$
5. **Step 4:** Calculate roots:
$$x_1 = \frac{-7 + 5}{4} = \frac{-2}{4} = -\frac{1}{2}$$
$$x_2 = \frac{-7 - 5}{4} = \frac{-12}{4} = -3$$
6. **Answer:** $x = -\frac{1}{2}$ or $x = -3$.
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1. **Problem:** Solve $2(x - 3)^2 - 5 = 7$.
2. **Step 1:** Add 5 to both sides:
$$2(x - 3)^2 = 12$$
3. **Step 2:** Divide both sides by 2:
$$\cancel{2}(x - 3)^2 = \frac{12}{\cancel{2}} \implies (x - 3)^2 = 6$$
4. **Step 3:** Take square root:
$$x - 3 = \pm \sqrt{6}$$
5. **Step 4:** Solve for $x$:
$$x = 3 \pm \sqrt{6}$$
6. **Answer:** $x = 3 + \sqrt{6}$ or $x = 3 - \sqrt{6}$.
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1. **Problem:** Solve $2x^2 - 6x = 0$.
2. **Step 1:** Factor out $2x$:
$$2x(x - 3) = 0$$
3. **Step 2:** Set each factor to zero:
$$2x = 0 \implies x = 0$$
$$x - 3 = 0 \implies x = 3$$
4. **Answer:** $x = 0$ or $x = 3$.
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1. **Problem:** Solve $(x - 1)^2 - 2 = -3$.
2. **Step 1:** Add 2 to both sides:
$$(x - 1)^2 = -3 + 2 = -1$$
3. **Step 2:** Take square root:
$$x - 1 = \pm \sqrt{-1} = \pm i$$
4. **Step 3:** Solve for $x$:
$$x = 1 \pm i$$
5. **Answer:** $x = 1 \pm i$.
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1. **Problem:** Solve $5x^2 - 16x + 10 = 0$.
2. **Step 1:** Use quadratic formula with $a=5$, $b=-16$, $c=10$.
3. **Step 2:** Calculate discriminant:
$$(-16)^2 - 4(5)(10) = 256 - 200 = 56$$
4. **Step 3:** Substitute:
$$x = \frac{16 \pm \sqrt{56}}{10} = \frac{16 \pm 2\sqrt{14}}{10}$$
5. **Step 4:** Simplify:
$$x = \frac{8 \pm \sqrt{14}}{5}$$
6. **Answer:** $x = \frac{8 + \sqrt{14}}{5}$ or $x = \frac{8 - \sqrt{14}}{5}$.
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1. **Problem:** Solve $x^2 - 2x + 10 = 0$.
2. **Step 1:** Use quadratic formula with $a=1$, $b=-2$, $c=10$.
3. **Step 2:** Calculate discriminant:
$$(-2)^2 - 4(1)(10) = 4 - 40 = -36$$
4. **Step 3:** Substitute:
$$x = \frac{2 \pm \sqrt{-36}}{2} = \frac{2 \pm 6i}{2}$$
5. **Step 4:** Simplify:
$$x = 1 \pm 3i$$
6. **Answer:** $x = 1 \pm 3i$ (complex roots).
Quadratic Log Solutions Ddc5Cd
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