SOLUTION: the cubed root of (2x+3) + 5= 2. I was told the answer is -15, but can't figure out how to get there. This is what I have tried. (2x+3)^3+5^3=2^3. Put both sides to the 3rd

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Question 341839: the cubed root of (2x+3) + 5= 2. I was told the answer is -15, but can't figure out how to get there. This is what I have tried.
(2x+3)^3+5^3=2^3. Put both sides to the 3rd power to undo the cubed root.
8x^3+125=8. Simplified.
8x^3= -117 Subtract 125 from both sides.
x^3= -117/8 Divide both sides by 8.
x^3= -14.625
x= cubed root of (-14.625)
x= i(2.445)
As you can tell I'm doing something totally wrong because I am WAY off.

Answer by Fombitz(32388)   (Show Source): You can put this solution on YOUR website!
No,no,no.
If and you cube both sides, you get .
You can't just cube the individual terms, you're missing cross terms.
.
.
.


Now cube both sides,



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