Let's solve each question step-by-step.
Question 1
To solve the quadratic equation \(x^2 + 2x - 8 = 0\) using the quadratic formula, \(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\):
- Here, \(a = 1\), \(b = 2\), and \(c = -8\).
- First, calculate the discriminant: \(b^2 - 4ac = 2^2 - 4(1)(-8) = 4 + 32 = 36\).
- Now apply the quadratic formula: \[ x = \frac{-2 \pm \sqrt{36}}{2(1)} = \frac{-2 \pm 6}{2} \]
- This results in: \[ x = \frac{4}{2} = 2 \quad \text{and} \quad x = \frac{-8}{2} = -4 \]
So, the solutions are \(x = 2\) and \(x = -4\). Response: x=2, x=−4
Question 2
To solve the quadratic equation \(x^2 - 22x + 1 = 15\), first rearrange it to standard form: \[ x^2 - 22x - 14 = 0 \] Now apply the quadratic formula with \(a = 1\), \(b = -22\), and \(c = -14\):
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The discriminant is: \[ b^2 - 4ac = (-22)^2 - 4(1)(-14) = 484 + 56 = 540 \]
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Apply the formula: \[ x = \frac{22 \pm \sqrt{540}}{2} \] Simplifying \(\sqrt{540} = \sqrt{36 \cdot 15} = 6\sqrt{15}\): \[ x = \frac{22 \pm 6\sqrt{15}}{2} = 11 \pm 3\sqrt{15} \] Calculating the approximations:
\(x \approx 11 + 3(3.87298) \approx 11 + 11.61894 \approx 22.61894\) and \(x \approx 11 - 11.61894 \approx -0.61894\).
Thus, the solutions are approximately \(x \approx 22.61895\) and \(x \approx -0.61895\). Response: x=22.61895004, x=−0.6189500386
Question 3
To solve \(x^2 - 6x - 16 = 0\) using the quadratic formula with \(a = 1\), \(b = -6\), and \(c = -16\):
- The discriminant is: \[ (-6)^2 - 4(1)(-16) = 36 + 64 = 100 \]
- Applying the quadratic formula: \[ x = \frac{-(-6) \pm \sqrt{100}}{2(1)} = \frac{6 \pm 10}{2} \]
- This results in: \[ x = \frac{16}{2} = 8 \quad \text{and} \quad x = \frac{-4}{2} = -2 \]
Responses: x=8, x=−2
Question 4
The equation \(2x^2 - 5x = 6\) rearranged becomes \(2x^2 - 5x - 6 = 0\). Now set \(a = 2\), \(b = -5\), and \(c = -6\):
- Discriminant: \[ (-5)^2 - 4(2)(-6) = 25 + 48 = 73 \]
- Using the quadratic formula: \[ x = \frac{-(-5) \pm \sqrt{73}}{2(2)} = \frac{5 \pm \sqrt{73}}{4} \]
- Approximating \(\sqrt{73} \approx 8.544\): \[ x \approx \frac{5 + 8.544}{4} \approx 3.886 \quad \text{and} \quad x \approx \frac{5 - 8.544}{4} \approx -0.886 \]
Thus, rounding to the nearest hundredth gives approximately \(x \approx 0.89\) and \(x \approx -1.03\). Response: x=−1.03
Question 5
For the quadratic equation \(4x^2 + x + 3 = 0\):
- The discriminant: \[ 1^2 - 4(4)(3) = 1 - 48 = -47 \] Since the discriminant is negative, there are no real solutions. Response: no real solutions