# Solve For x

Discussion in 'Other Pre-University Math' started by nycmathguy, Nov 12, 2021.

1. ### nycmathguy

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Review

nycmathguy, Nov 12, 2021

2. ### MathLover1

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..........convert to same base

...if base same, exponents are same too

MathLover1, Nov 12, 2021

3. ### HallsofIvy

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8^{x- 3}= (2^3)^{x- 3}= 2^{3x- 9} NOT 2^{2x- 6}
so the next line is
2^{5x- 7}= 2^{12x- 28}

5x- 7= 12x- 28
-7+ 28= 12x- 5x
21= 7x
x= 3!

HallsofIvy, Nov 12, 2021
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4. ### MathLover1

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thanks!!!!! evidently I need new glasses

MathLover1, Nov 12, 2021
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5. ### MathLover1

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doing one correction

5x-7=12x-28
28-7=12x-5x
21=7x
x=3

MathLover1, Nov 12, 2021
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6. ### nycmathguy

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nycmathguy, Nov 13, 2021

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