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)
Direct Proportion functions look like this:
y=kx
'k' is the constant of proportionality and in this case its 7.5 or 15/2.
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When x=1, y=7.5
When x=2, y=15
When x=3, y=22.5
Therefore y is directly proportional to x.
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DIRECT PROPORTION EXPLAINED:
Say a football costs £7.50. If you buy one football you'll have to pay out £7.50, but if you you buy two footballs you'll have to pay out £15.00. Therefore the cost of the football(s) is directly proportional to the amount of footballs you buy. C=cost, f=football(s) and C<span>∝f, therefore C=kf, but as k=7.5, C=7.5f.
INVERSE PROPORTION EXPLAINED:
If it were to take 8 hours for one bricklayer to set up a wall, how long would it take for two bricklayers to set up a wall? The answer in this case would be 4 hours.
T=time to set up a wall
b=bricklayer(s)
Therefore T</span><span>∝1/b, and T=k/b. In this case k=8 so T=8/b.
When b=1, T=8.
When b=2, T=4.
We'd say that the time it would take for bricklayers to set up a wall would be inversely proportional to the amount of bricklayers available.</span>
There is a problem with your question. it doesn't make sense ???
Find any two points on the line.
<span>x=0⇒y=4<span>(0)</span>+7=7⇒</span> Point 1: <span>(0,7)</span>
<span>x=−1⇒y=4<span>(−1)</span>+7=3⇒</span> Point 2: <span>(−1,3)</span>
Step 2: Plot the two points from Step 1
Step 3: Draw a straight line through both points
Answer:
$0.64
Step-by-step explanation:
Unit price is the cost of a single metre of ribbon
5.12/8=0.64