SOLUTION: PLEASE HELP ME: Solve the equation 4^2x+1=2^3x+6

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Question 55488: PLEASE HELP ME:
Solve the equation 4^2x+1=2^3x+6

Found 2 solutions by funmath, Genius:
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation
4%5E%282x%2B1%29=2%5E%283x%2B6%29 4 is 2^2 so...
%282%5E2%29%5E%282x%2B1%29=2%5E%283x%2B6%29
%282%29%5E%282%282x%2B1%29%29=2%5E%283x%2B6%29 Since the bases are equal their exponents are equal:
2%282x%2B1%29=%283x%2B6%29
4x%2B2=3x%2B6
-3x%2B4x%2B2=-3x%2B3x%2B6
x%2B2=6
x%2B2-2=6-2
highlight%28x=4%29
Check by substitution:
4%5E%282%284%29%2B1%29=2%5E%283%284%29%2B6%29
4%5E%288%2B1%29=2%5E%2812%2B6%29
4%5E9=2%5E18
262144=262144 We're right!!!
Happy Calculating!!!

Answer by Genius(17) About Me  (Show Source):
You can put this solution on YOUR website!
First, let's work on the left hand side of your equation, the 4^2x+1
This means, for instance, to see if it can be simplified at all.


16
Multiply x and 16
Multiply x and 1



The x just gets copied along.
x
x


16x

16x+1
So, all-in-all, the left hand side of your equation can be written as: 16x+1

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Now, let's work on the right hand side of your equation, the 2^3x+6


8
Multiply x and 8
Multiply x and 1


The x just gets copied along.
x
x

8x

8x+6
The right hand side of your equation can be written as: 8x+6

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So with these (any) simplifications, the equation we'll set out to solve is:
16x+1 = 8x+6

Move the 1 to the right hand side by subtracting 1 from both sides, like this:

From the left hand side:
1 - 1 = 0


16x
From the right hand side:
6 - 1 = 5


5+8x
Now, the equation reads:
16x = 5+8x
Move the 8x to the left hand side by subtracting 8x from both sides, like this:
From the left hand side:
16x - 8x = 8x

8x
From the right hand side:
8x - 8x = 0


5
Now, the equation reads:
8x = 5
To isolate the x, we have to divide both sides of the equation by the other variables
around the x on the left side of the equation.


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The last step is to divide both sides of the equation by 8 like this:
To divide x by 1



The x just gets copied along in the numerator.

x
8x ÷ 8 = x

5 ÷ 8 = 5/8 or 0.625
The solution to your equation is:
x = 5/8 or 0.625