1. **Problem a:** Solve the quadratic equation $$-3x + \frac{6}{7} = 9x^2$$ and find its roots.
2. **Step 1:** Rearrange the equation to standard quadratic form $$ax^2 + bx + c = 0$$.
$$9x^2 + 3x - \frac{6}{7} = 0$$
3. **Step 2:** Identify coefficients: $$a = 9, b = 3, c = -\frac{6}{7}$$.
4. **Step 3:** Use the quadratic formula:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
5. **Step 4:** Calculate the discriminant:
$$\Delta = b^2 - 4ac = 3^2 - 4 \times 9 \times \left(-\frac{6}{7}\right) = 9 + \frac{216}{7} = \frac{63}{7} + \frac{216}{7} = \frac{279}{7}$$
6. **Step 5:** Calculate roots:
$$x = \frac{-3 \pm \sqrt{\frac{279}{7}}}{18} = \frac{-3 \pm \frac{\sqrt{279}}{\sqrt{7}}}{18} = \frac{-3 \pm \frac{\sqrt{279}}{\sqrt{7}}}{18}$$
7. **Step 6:** Simplify the roots:
$$x = \frac{-3}{18} \pm \frac{\sqrt{279}}{18\sqrt{7}} = -\frac{1}{6} \pm \frac{\sqrt{279}}{18\sqrt{7}}$$
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8. **Problem b:** There are three consecutive integers. The product of the two larger integers is 3660. Find the three integers.
9. **Step 1:** Let the three consecutive integers be $$x$$, $$x+1$$, and $$x+2$$.
10. **Step 2:** The product of the two larger integers is:
$$(x+1)(x+2) = 3660$$
11. **Step 3:** Expand and form quadratic equation:
$$x^2 + 3x + 2 = 3660$$
$$x^2 + 3x + 2 - 3660 = 0$$
$$x^2 + 3x - 3658 = 0$$
12. **Step 4:** Use quadratic formula with $$a=1$$, $$b=3$$, $$c=-3658$$:
$$x = \frac{-3 \pm \sqrt{3^2 - 4 \times 1 \times (-3658)}}{2} = \frac{-3 \pm \sqrt{9 + 14632}}{2} = \frac{-3 \pm \sqrt{14641}}{2}$$
13. **Step 5:** Calculate $$\sqrt{14641} = 121$$.
14. **Step 6:** Find roots:
$$x = \frac{-3 \pm 121}{2}$$
- Positive root: $$x = \frac{-3 + 121}{2} = \frac{118}{2} = 59$$
- Negative root: $$x = \frac{-3 - 121}{2} = \frac{-124}{2} = -62$$
15. **Step 7:** The three consecutive integers are either $$59, 60, 61$$ or $$-62, -61, -60$$.
16. **Step 8:** Verify product:
$$60 \times 61 = 3660$$ and $$-61 \times -60 = 3660$$ both true.
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**Use of AI:**
- I used AI tools like ChatGPT to verify the quadratic formula steps and to confirm the factorization and root calculations.
- AI helped me understand how to set up the equations from word problems and check arithmetic.
- I referred to recorded video lectures on Quadratic Equations to ensure correct application of formulas and problem-solving strategies.
**Final answers:**
- a) Roots are $$x = -\frac{1}{6} \pm \frac{\sqrt{279}}{18\sqrt{7}}$$.
- b) The three consecutive integers are either $$59, 60, 61$$ or $$-62, -61, -60$$.
Quadratic Roots B3443E
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