Please help me solve: 7^(2x + 1) - 4*7^(2x) = 1029

AlphaBlaziken

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72x+1 - 4(72x) =1029
I think the first step should be
72x+1-22.72x = 3.73 what should i do with the 22 and 3?
If there aren't 2 and 3 I can just make it like this 2x+1-2x = 3 right?
Thanks.
 
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Help me with this plese. (Exponent)

72x+1-4(72x) = 1029 I guess the first step should be
72x+1-22.72x = 3.73 What should I do next?
I can't just make it like 2x+1-2x = 3 right?
Thanks.
 
72x+1 - 4(72x) =1029
I think the first step should be
I will guess that the instructions were to "solve the equation".

72x+1-22.72x = 3.73 what should i do with the 22 and 3?
I will guess that you are using decimal points to represent multiplication, so the above is actually as follows:

. . . . .\(\displaystyle 7^{2x+1}\, -\, (2^2)(7^{2x})\, =\, (3)(7^3)\)

If there aren't 2 and 3 I can just make it like this 2x+1-2x = 3 right?
I'm sorry, but I can't guess what this means...?

You have a right-hand side which neatly factors into primes:

. . . . .\(\displaystyle 1,029\, =\, (3^1)(7^3)\)

This (strongly!) suggests that the left-hand side should be converted to the two same primes. So try that:

. . . . .\(\displaystyle 7^{2x+1}\, =\, (7^{2x})(7^1)\, =\, 7(7^{2x})\)

This means that the left-hand side is:

. . . . .\(\displaystyle 7(7^{2x})\, -\, 4(7^{2x})\)

If they'd have given you this:

. . . . .\(\displaystyle 7y\, -\, 4y\)

...how would you have simplified? Then how can you simplify what they gave you here? Then where does this lead? ;)
 
Oooh. Thank You so much. I didn't realize that you could do that. I'm still new at this sorry.
It's like this right
3(72x)=3(73)
X = 3/2 THANK YOU
 
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