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Solve 𝑥 cubed plus five equals nine.
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Well, the first thing we wanna do when solving an equation in this form is actually get the 𝑥 term on its own.
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So to do that, the first thing we’re gonna do is actually subtract five from each side of our equation.
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So that’s gonna give us 𝑥 cubed is equal to four.
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Because if we have plus five minus five, that’s gonna be zero.
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And if we have nine minus five, we get four.
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Okay, great.
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So now, we’ve got 𝑥 cubed equals four.
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So now, what we’re gonna do is actually inverse of cube because we’ve got 𝑥 cubed.
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So what we’re gonna do is cube-root each side.
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So therefore, we can say that 𝑥 — because if you cube-root a cube, you’re just left with the original value or in this case 𝑥 — is gonna be equal to the cube root of four.
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So we’re actually gonna leave our answer in this form because we don’t wanna lose any accuracy by rounding.
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So therefore, we can say that the solution to 𝑥 cubed plus five equals nine is 𝑥 is equal to the cube root of four.