Aight, so the question is to "Solve the following equation". Unfortunately, I have no clue where to start... The equation is $\displaystyle 2^x + 2^{2x+3} =72 $ Thanks in advance.
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Originally Posted by ns2583 Aight, so the question is to "Solve the following equation". Unfortunately, I have no clue where to start... The equation is $\displaystyle 2^x + 2^{2x+3} =72 $ Thanks in advance. Note that $\displaystyle 2^{2x+3} = 2^3 \cdot 2^{2x} = 8 \cdot \left( 2^{x} \right)^2.$
Originally Posted by danny arrigo Note that $\displaystyle 2^{2x+3} = 2^3 \cdot 2^{2x} = 8 \cdot \left( 2^{x} \right)^2.$ I still don't know what goes next? Sorry.
Originally Posted by ns2583 I still don't know what goes next? Sorry. So $\displaystyle 2^x + 8 \cdot \left( 2^{x} \right)^2 = 72,$ If we let $\displaystyle y = 2^x$ we get a quadratic equation for y.
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