This is a precalculus problem. Please help me solve!
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Looks scary, doesn't it? A closer inspection shows that the quantity (2x+5)^3 appears on both sides of the equation. Put it to one side and remove it from both sides: 4x(2x-1)^1/3=6x(2x-1)^2/3. This can be further simplified by dividing both sides by 2. We also have x on both sides. Put it to one side and remove it from both sides of the equation. We're left with 2(2x-1)^1/3=3(2x-1)^2/3. We can divide both sides by (2x-1)^1/3: 2=3(2x-1)^1/3. We just subtract the indices to do the division: 2/3-1/3=1/3. Finally, we're getting there. Cube both sides: 8=27(2x-1), so 8=54x-27 and 35=54x and x=35/54. But we're not through. The quantities we put to one side were x and (2x+5)^3. These represent solutions, too. When we remove quantities we are actually factorising and making the assumption that these quantities are not zero, when in fact zero is a solution; so x=0 and 2x+5=0, making x=-2.5, are solutions. So we have x=-2.5, 0, or 35/54 as solutions.

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