Answer:
as written: 7x^2
perhaps intended: 7x^4
Step-by-step explanation:
As written, the Order of Operations specifies that the only denominator factor is 3, so the expression is interpreted as ...

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Sometimes grouping of denominator factors is intended, but parentheses are not written as they should be. If the intention is ...
21x^3/(3x^-1)
then the simplification is ...

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The applicable rules of exponents are ...
(a^b)(a^c) = a^(b+c)
a^b/a^c = a^(b-c)
4/10 is 2/5 or 0.4 in decimal form.
Well the remainder more possible dividing by six would be 9.3 I hope i helped.
(13 + x)/(50 - x ) = (2/1)
Cross Multiply
2(50-x) = 1(13 + x)
100 - 2x = 13 + x
add 2x to both sides
100 -2x + 2x = 13 + x + 2x
100 = 13 + 3x
Subtract 13 from both sides
100 - 13 = 13 - 13 + 3x
87 = 3x
divide both sides by 3
29 = x
(13 + 29)/(50-29) = 42/21 = 2 to 1 ratio