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I need to know how to factor this equation 8x^3-125=0

1 Answer

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Final answer:

The equation 8x³ - 125 = 0 is a difference of cubes that can be factored and solved to find that x = 2.5.

Step-by-step explanation:

To factor the equation 8x³ - 125 = 0, we can observe that both terms are perfect cubes.

The first term, 8x³, is the cube of (2x), and the second term, -125, is the cube of (-5).

This equation is actually a difference of cubes, which can be factored using the formula a³ - b³ = (a - b)(a²+ ab + b²).

Applying this formula to our equation, where a is (2x) and b is 5, we get: (2x - 5)((2x)² + (2x)(5) + (5)²)

= (2x - 5)(4x² + 10x + 25)

Now that we have factored the equation, it is equal to zero when (2x - 5) is zero or when (4x²+ 10x + 25) is zero. However, since (4x² + 10x + 25) is always positive, the only solution comes from 2x - 5 = 0.

Solving for x, we get x = 2.5.

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