SOLUTION: SORRY I HAD ENTERED THE WRONG EMAIL ADDRESS.typo error hi there I am currently doing exponential equations and indices, which im understanding a few but unable to complete these.

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Question 662430: SORRY I HAD ENTERED THE WRONG EMAIL ADDRESS.typo error
hi there I am currently doing exponential equations and indices, which im understanding a few but unable to complete these. Can you assist?
1. 5^2x-6(5^x)+5=0
(5x)^2-6(5^x)+5=0
let 5x=y
y^2-6y+5=0
(this one i have started to work on but unable to finish)
2.4^x(5^2x)=10
3.7^x+1-2=2(7^x)+3
4.6(3^x-1)=3^4-3^x
I would greatly appreciate help thanks.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

1. 5^2x-6(5^x)+5=0

 (5x)^2-6(5^x)+5=0

 let 5x=y+    || Good work!

 y^2-6y+5=0

factoring

(y-5)(y-1) = 0,  y = 5 0r y = 1  AND   x = 1  0r x = 1/5

As to the Remainder: the Idea is combining Like Terms...

2.4^x(5^2x)=10  ⇒ 2%5E%282x%295%5E%282x%29+=+10%5E%282x%29+=+10, x = 1/2 

 3.7^x+1-2=2(7^x)+3 ⇒ 7^x(7-2) = 5 ⇒ 7^x = 1,   x = 0 

 4.6%283%5E%28x-1%29%29=3%5E4-3%5Ex ⇒ 

   3^x (6*3^(-1)+1) = 3^x(2+1)= 81  ⇒  3^x = 27,    x = 3