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What is the solution to 3x2 + 5x > –2? x < –1 or x is greater than negative two thirds x is greater than or equal to negative two thirds or x < 1 negative two thirds is less than or equal to x is less than or equal to 1 negative two thirds is greater than x is greater than negative 1

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Answer:

To solve the inequality 3x^2 + 5x > -2, we can follow these steps:

Move all the terms to the left-hand side to get 3x^2 + 5x + 2 > 0

Factor the quadratic expression by finding two numbers that multiply to 6 (3 times 2) and add to 5. These numbers are 3 and 2, so we can write: 3x^2 + 3x + 2x + 2 > 0

Group the first two terms and the last two terms: 3x(x + 1) + 2(x + 1) > 0

Factor out (x + 1): (x + 1)(3x + 2) > 0

Determine the sign of each factor by testing values of x:

When x < -1, both factors are negative, so the product is positive.

When -1 < x < -2/3, the first factor (x + 1) is positive, but the second factor (3x + 2) is negative, so the product is negative.

When x > -2/3, both factors are positive, so the product is positive.

Write the solution as an inequality based on the sign of the product: (x + 1)(3x + 2) > 0 is true when x < -1 or x > -2/3.

Therefore, the solution to the inequality 3x^2 + 5x > -2 is x < -1 or x > -2/3.

Step-by-step explanation:

User Dwayne Crooks
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