Solve ACT Word Problem: Find Value of x

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The discussion revolves around solving an ACT word problem involving two numbers, where the larger number exceeds twice the smaller by 8, and the sum of twice the larger and three times the smaller equals 65. The participant initially misinterpreted the relationship between the numbers, incorrectly setting up the equation for the larger number. After reviewing their steps, they realized that the correct formulation should have been y = 2x + 8 instead of y = 2x - 8. This correction led to the identification of the correct equation, which is option D, confirming the importance of accurately translating word problems into mathematical expressions. The participant expressed gratitude for the clarification and recognized their mistake.
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I'm studying for the ACT and this was one of the practice test problems. The book does offer an explanation for how to get the answer but it isn't very detailed and I still don't know what I'm doing wrong.

Homework Statement


The larger of two numbers exceeds twice the smaller number by ##8##. The sum of twice the larger and ##3## times the smaller number is ##65##. If ##x## is the smaller number, which equation below determines the correct value of ##x##?

A. ##3(2x+8)+2x=65##
B. ##3(2x-8)+2x=65##
C. ##(4x+8)+3x=65##
D. ##2(2x+8)+3x=65##
E. ##2(2x-8)+3x=65##​

(According to the book, the correct answer is D.)

2. Homework Equations

To be consistent with the book, I'll let the larger number be ##y##, and the smaller number be ##x##.

The Attempt at a Solution


Taking this one step at a time:

The larger of two numbers exceeds twice the smaller number by ##8##.
I think this translates into ##y+8=2x##.

The sum of twice the larger and ##3## times the smaller number is ##65##.
So this means that ##2y+3x=65##. Now, because they want the answer to be in terms of ##x##, I need to rewrite ##y## in terms of ##x## (which is ##y=2x-8##) and plug that into the formula.

Then it becomes ##2(2x-8)+3x=65##. This is answer option E, but apparently this is isn't the right answer.​

Please, look over my steps and see if you can spot what I missed. The correct answer, D, differs only by the sign inside the parenthesis. I don't see what I'm doing wrong, and I'm really confused as to how they got ##+8##. Thank you.
 
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If ##y## exceeds ##2x## by ##8## then ##y = 2x + 8##.
 
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PeroK said:
If ##y## exceeds ##2x## by ##8## then ##y = 2x + 8##.

Ohh... so I must've messed up at the first step then. I think I see what I did wrong now: to show that ##y## was greater than ##2x## by ##8##, I should have added the 8 on the other side of the equation. Dumb mistake on my part. Thanks!
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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