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Formula
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Circumference = πD
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Find Diameter
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3600π = πD
D = 3600 ← Divide by π on both sides
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Answer: Diameter = 3600 unit
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Answer:
n=4
Step-by-step explanation:
f(x+n)=3(x+n)^2-7=3x^2+24x+41
3x^2+3n^2+6xn-7=3x^2+24x+41
Comparing and we will get, n=4

The rule I'm using is

note how I rewrote "3" into the square root of 9, so that everything would have a square root over it, and that allows me to use that rule above.
1(x + 3) + 3(x - 1) = 20
1(x) + 1(3) + 3(x) - 3(1) = 20
x + 3 + 3x - 3 = 20
x + 3x + 3 - 3 = 20
4x = 20
4 4
x = 5