When y=125 and x=-3, what is the value of $root3y-3x^4$ ?

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Answer 1 · 2017-01-06T03:02:49

Let $x=-3$
Let $y=125$
$root3(y)-3x^4=$

$-238$

$root3(y) -3x^4$

Let's break this down starting with $y$ .

$root3(125) = 5$
because $n*n*n = n^3$ and $root3(n^3)=n$ .

$5^3=125$ [how convenient :)]

$root3(125)=5$

Now $x$ .

$3(-3)^4$

Recall PEMDAS: Parentheses first, then exponents. You have to take account for that negative.

$-3*-3*-3*-3 = 81$

$81*3=243$

Finally:

$5 - 243 = -238$

When y=125 and x=-3, what is the value of root3y-3x^4root3y-3x^4?