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The graph of log10y against x is a straight line
Then it shows a point of (4,6) and a y intercept of 2.

i) find the equation for log10y in terms of x

ii) find the equation for y in terms of x
(edited 1 year ago)
Reply 1
Original post by Nithu05
The graph of log10y against x is a straight line
Then it shows a point of (4,6) and a y intercept of 2.

i) find the equation for log10y in terms of x

ii) find the equation for y in terms of x

I got log10y=x+2. Is this right?
Reply 2
However, in the mark scheme is says log10y=3x+2. Could someone please explain?
Have you tried putting the point (4,6) into your equation?
Reply 4
Original post by qweqworiet
Have you tried putting the point (4,6) into your equation?

I worked out the gradient using the points (4,6) and (0,2). However, the mark scheme says the gradient is 3. Could you please explain?
Reply 5
Original post by Nithu05
The graph of log10y against x is a straight line
Then it shows a point of (4,6) and a y intercept of 2.

i) find the equation for log10y in terms of x

ii) find the equation for y in terms of x

Can you upload a picture of the original question?
(edited 1 year ago)
Reply 6
Original post by John mburu
I can help with the step by step calculation on how to go about it.


Ok couldn't you just post the answer here?
Reply 7
Original post by Skiwi
Can you upload a picture of the original question?


Here’s the picture
Reply 8
Original post by John mburu
okay let me work on it in my book and the I will post it.


Thank you so much
Original post by Nithu05
Thank you so much


I agree with your answer.
No charge.
Reply 10
Original post by mqb2766
I agree with your answer.
No charge.


So is the mark scheme wrong?
Original post by Nithu05
So is the mark scheme wrong?


Would appear so.
log10(y) = 6
means y = 10^6, whcih is not 10^(3*4+2).
(edited 1 year ago)
Reply 12
Original post by mqb2766
Would appear so.


Thanks so much. Could you please check my other post on a vector question?
Original post by Nithu05
Thanks so much. Could you please check my other post on a vector question?

Ok, I edited the previous post slightly as you were replying.
Reply 14
Original post by Nithu05
Thanks so much. Could you please check my other post on a vector question?


https://www.thestudentroom.co.uk/showthread.php?t=7228005&p=97314805#post97314805
Reply 15
Original post by John mburu
IMG-20220617-WA0008-compressed.jpg.jpeg
follow me on Instagram for more @George_ruben12

Thank you! Although, we haven't learnt antilogs yet.

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