Question 144318
To equate the powers you have to have equal bases:
y=3^(2x+1)
y=9^(4-2x) 
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y = 3^(2x+1)
y = 3^[2(4-2x)]
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2x+1 = 2(4-2x)
2x+1 = 8-4x
6x = 7
x = 7/6
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Cheers,
Stan H.