What are the solutions to the quadratic equation 3x^2 + 42x + 75 = 0?

To find the solutions to the quadratic equation 3x² + 42x + 75 = 0, we can use the quadratic formula, which is given by:

x = (-b ± √(b² – 4ac)) / 2a

In this equation, the coefficients are:

  • a = 3
  • b = 42
  • c = 75

First, we need to calculate the discriminant (b² – 4ac):

1. Calculate :
42² = 1764

2. Calculate 4ac:
4 * 3 * 75 = 900

3. Now, calculate the discriminant:
b² – 4ac = 1764 – 900 = 864

Since the discriminant is positive, we can expect two real solutions. Now we can plug in the values into the quadratic formula:

x = (-42 ± √864) / (2 * 3)

First, we simplify:

√864 can be simplified to √(144 × 6) = 12√6.

Now, substitute that back into our equation:

x = (-42 ± 12√6) / 6

This simplifies to:
x = -7 ± 2√6

Thus, the two solutions to the quadratic equation 3x² + 42x + 75 = 0 are:

  • x = -7 + 2√6
  • x = -7 – 2√6

In decimal form, these approximate to:

  • x ≈ -3.898
  • x ≈ -10.102

So the complete solution set is { -7 + 2√6, -7 – 2√6 }.

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