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Jun 18, 2017
 #2
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Jun 18, 2017
 #2
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Let me try to do this. If I am not mistaken, this is the original equation:

 

\(2^{3x}*\frac{8^{x+3}}{16^{x-1}}=2^{\frac{x-1}{2}}\)

 

\(2^{3x}*\frac{8^{x+3}}{16^{x-1}}=2^{\frac{x-1}{2}}\)Our first step, I think, is to get rid of the fraction. I'm going to use the rule that \(\frac{1}{a^b}=a^{-b}\)
\(\frac{1}{16^{x-1}}=16^{-(x-1)}=16^{-x+1}\)Doing this puts allows me to take this out of the fraction. Therefore, I am going to rewrite the current equation
\(2^{3x}*8^{x+3}*16^{-x+1}=2^{\frac{x-1}{2}}\)Now, convert \(8^{x+3}\)into a form where it will be in base 2. Luckily for us, all these numbers can be in that form. 
\(8^{x+3}=(2^3)^{x+3}\)Okay, let's insert that back into the equation.
\(2^{3x}*(2^3)^{x+3}*16^{-x+1}=2^{\frac{x-1}{2}}\)Now, convert \(16^{-x+1}\) into base 2, as well. 
\(16^{-x+1}=(2^4)^{-x+1}\)Insert that into the original equation again, too.
\(2^{3x}*(2^3)^{x+3}*(2^4)^{-x+1}=2^{\frac{x-1}{2}}\)Now, I'll apply a rule on the term \((2^3)^{x+3}\) that says that \((a^b)^c=a^{b*c}\). Let's use it.
\((2^3)^{x+3}=2^{3(x+3)}\)Insert it into the original equation.
\(2^{3x}*2^{3(x+3)}*(2^4)^{-x+1}=2^{\frac{x-1}{2}}\)Now, I'll use another power rule that says that \(a^b*a^c=a^{b+c}\). I'll utilize this for \(2^{3x}*2^{3(x+3)}\)
\(2^{3x}*2^{3(x+3)}=2^{3x+3(x+3)}\)Reinsert this back into the equation.
\(2^{3x+3(x+3)}*(2^4)^{-x+1}=2^{\frac{x-1}{2}}\)Okay, now the only term left is \((2^4)^{-x+1}\). Just like before, we'll use an exponent rule that says that \((a^b)^c=a^{b*c}\).
\((2^4)^{-x+1}=2^{4(-x+1)}\)Insert this back into the equation again.
\(2^{3x+3(x+3)}*2^{4(-x+1)}=2^{\frac{x-1}{2}}\)Yet again, we'll utilize the same rule as before that says that \(a^b*a^c=a^{b+c}\).
\(2^{3x+3(x+3)}*2^{4(-x+1)}=2^{3x+3(x+3)+4(-x+1)}\)Reinsert this into the equation again.
\(2^{3x+3(x+3)+4(-x+1)}=2^{\frac{x-1}{2}}\)Now, we'll use another rule that says that\(a^{f(x)}=a^{g(x)},\text{then}\hspace{1mm}f(x)=g(x)\). This will reduce the equation to simply two-sided equation without exponents.
\(3x+3(x+3)+4(-x+1)=\frac{x-1}{2}\)To clean this up, let's use the distribute property.
\(3x+3x+9-4x+4=\frac{x-1}{2}\)Combine like terms on the left hand side of the equation.
\(2x+13=\frac{x-1}{2}\)Multiply both sides by 2 to get rid of the pesky fraction.
\(4x+26=x-1\)Subtract x on both sides.
\(3x+26=-1\)Subtract 26 on both sides
\(3x=-27\)Divide by 3 on both sides to finally isolate x.
\(x=-9\) 
  
Jun 18, 2017

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