This is easy. All you need to do is set up a <u><em>proportional relationship</em></u>.
A proportional relationship uses variables to show similarities, in this case, in triangles.
<u><em>x</em></u> represents the missing side.
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)