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# Need help solving an equation watch

1. Solve the equation. 25^x = 5^4x+1

2. 25 can be simplified into a power of 5. Make sure to use brackets when doing so to avoid confusion.
3. (Original post by ghost88)
Solve the equation. 25^x = 5^4x+1

Since then

A simple substitution of yields

Which is a simple quadratic, solve and then back-substiute.
4. (Original post by Zacken)
Since then

A simple substitution of yields
Which is a simple quadratic, solve and then back-substiute.
It's even simpler than that:
25^x = 5^4x+1
if 25^x=5^2x
then 2x=4x+1
therefore you can -2x and -1 hence, 2x=-1
then /2 giving x=-1/2
5. (Original post by 04MR17)
It's even simpler than that:
25^x = 5^4x+1
if 25^x=5^2x
then 2x=4x+1
therefore you can -2x and -1 hence, 2x=-1
then /2 giving x=-1/2
Ah, I think we might be at a cross-roads here. I'm reading the equation as , you're reading it as - it's up to the OP to clarify here.
6. (Original post by Zacken)
Ah, I think we might be at a cross-roads here. I'm reading the equation as , you're reading it as - it's up to the OP to clarify here.
I've been doing these last week, if it's C1 AS it'll probably be my way. If it's anything above you'll be right I Reckon Zacken.
7. (Original post by 04MR17)
I've been doing these last week, if it's C1 AS it'll probably be my way. If it's anything above you'll be right I Reckon Zacken.
In either case, I'll be annoyed at the OP for his ambiguity.
8. (Original post by Zacken)
In either case, I'll be annoyed at the OP for his ambiguity.
Even so, the winner gets a rep.
9. (Original post by 04MR17)
Even so, the winner gets a rep.
May the best guesser win.
I don't mind if you get the rep.
10. (Original post by ghost88)
Solve the equation. 25^x = 5^4x+1

Use logs , or rules of indicies
25^x is the same as 5^2
So x^2 = 4x +1
Then reaarange for quadratic and solve
11. Make both powers in base 5 and put the powers equal then solve
12. The ghost88 has become a ghost ...
13. Sorry guys, I moved on to Economics and forgot to check . And Yeah its C1.

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