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Maths C2 help watch

1. Hello I am really struggling with this question, wonder could anyone solve this for me?
log6 + log(x-3) =2 log y
2y -x =3

thanks

===Moved to Maths===
2. (Original post by Marcus2016)
Hello I am really struggling with this question, wonder could anyone solve this for me?
log6 + log(x-3) =2 log y
2y -x =3

thanks

===Moved to Maths===
I'm not going to solve it for you, but I will give you a starting step/hint:

Can you use the equation to express in terms of , or just an equation linking the two?

Then it's just solving simultaneous equations from C1!!
3. (Original post by crashMATHS)
I'm not going to solve it for you, but I will give you a starting step/hint:

Can you use the equation to express in terms of , or just an equation linking the two?

Then it's just solving simultaneous equations from C1!!
Thanks but when i multiply log into the bracket what does it become, is it log -3, as you can't get a negative log?
4. remember....

log p + log q = log pq

alog p = log {pa}
5. (Original post by Marcus2016)
Thanks but when i multiply log into the bracket what does it become, is it log -3, as you can't get a negative log?
Oh no, you have a misunderstanding. It is generally not true that . That is not how logarithms work.

What you want to be using is that: for the left hand side. In this case, let your
6. Thanks everyone question solved I owe you one!
7. sorry to ask again but any hints for the following?

2 + log2(2x +1) =2 log2 y
x=22-y
8. (Original post by Marcus2016)
sorry to ask again but any hints for the following?

2 + log2(2x +1) =2 log2 y
x=22-y

Then apply log rules and get rid off the logs.
9. (Original post by Marcus2016)
sorry to ask again but any hints for the following?

2 + log2(2x +1) =2 log2 y
x=22-y
RDKgames has suggested a nice method or you may like to rearrange the first equation to:

and use the rule that
10. Thanks again!!!

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