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Maths help

How would I do this question?

"Rearrange y = 16 - 4x to make x the subject."
Original post by Jack_Tomlin
How would I do this question?

"Rearrange y = 16 - 4x to make x the subject."


How would you go about doing it?

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Original post by Jack_Tomlin
How would I do this question?

"Rearrange y = 16 - 4x to make x the subject."


Start by moving everything except 4x on one side, then divide through
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Original post by HopelessMedic
Start by moving everything except 4x on one side, then divide through


Ok so far I've got - 16y = -4x
Is x = -4?
You should have taken 16 away from both sides to leave y-16=-4x. The divide through to get x in terms of y
Original post by Jack_Tomlin
Ok so far I've got - 16y = -4x
Is x = -4?


Remember that you are not solving for an actual value for x, you just want to find what x is in terms of y.
In your answer you correctly subtracted 16 from the RHS, but have not done the same on the LHS. Instead, you've multiplied the LHS by -16.
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Original post by surina16
Remember that you are not solving for an actual value for x, you just want to find what x is in terms of y.
In your answer you correctly subtracted 16 from the RHS, but have not done the same on the LHS. Instead, you've multiplied the LHS by -16.


Ok would you mind answering the question so I can see all the steps?
Original post by Jack_Tomlin
Ok would you mind answering the question so I can see all the steps?


Sure.

y = 16 - 4x
[-16]
y - 16 = -4x
[*-1]
16 - y = 4x

(16-y)/4 = x

you can leave it like that, or you can divide the 16 by the 4 to simplify it:
x = 4 - y/4
or
x = 4 - 0.25y which looks tidier imo :h:
Reply 8
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Original post by surina16
Sure.

y = 16 - 4x
[-16]
y - 16 = -4x
[*-1]
16 - y = 4x

(16-y)/4 = x

you can leave it like that, or you can divide the 16 by the 4 to simplify it:
x = 4 - y/4
or
x = 4 - 0.25y which looks tidier imo :h:

Thanks

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