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**harpazo1965****Member**- Registered: 2022-09-19
- Posts: 68

Solve for a.

30 = 26 - (a/6).

I need to remove that fraction on the right for easy solving.

I will rewrite the equation this way:

30 = (26/1) - (a/6)

The LCD = 6. Multiply every term on both sides of the equation by 6.

6(30) = (26/1)(6) - (a/6)(6)

180 = 156 - a

180 - 156 = - a

24 = - a

24/(-1) = - a/(-1)

-24 = a

You say?

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 39,688

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**harpazo1965****Member**- Registered: 2022-09-19
- Posts: 68

ganesh,

Are you saying that my way is too lengthy?

This is a math homework questions that one of

my kids couldn't solve. Is my way too lengthy for an 8th grader?

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 39,688

Hi harpazo1965,

All I say is it can be solved in fewer steps.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**Phrzby Phil****Member**- From: Richmond, VA
- Registered: 2022-03-29
- Posts: 7

Try undoing the operations in reverse precedence order to isolate the variable.

World Peace Thru Frisbee

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 39,688

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**Bob****Administrator**- Registered: 2010-06-20
- Posts: 9,584

hi harpazo1965

Generally any solution is acceptable. Many years ago I did some Advance Level marking for the UK EdExcel exam board. There was one question that specified the method to be used and the chief examiner said any candidate who used another method should get no marks! That is very unusual.

I would have used the same method as you but written less steps:

30 = 26 - (a/6)

(times by 6)

180 = 156 - a

(re-arrange)

a = 156 - 180 = -24

which is just 3 lines, same as Ganesh.

This equation is 'linear' meaning if you plot the graph y = 26 - a/6 you get a straight line. The line y = 30 will cross it in just one place, so there is exactly one solution. Sometimes you may spot a solution 'by inspection'. It is acceptable to state this and then show it works:

I notice that -24 looks like a solution.

check 26 - (-24/6) - 26 + 4 = 30. As this equation is linear this is the solution. That's a two line answer

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Sometimes I deliberately make mistakes, just to test you! …………….Bob

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**harpazo1965****Member**- Registered: 2022-09-19
- Posts: 68

ganesh wrote:

Hi harpazo1965,

All I say is it can be solved in fewer steps.

Ok. Thanks.

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**harpazo1965****Member**- Registered: 2022-09-19
- Posts: 68

Phrzby Phil wrote:

Try undoing the operations in reverse precedence order to isolate the variable.

Very good.

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