x is:

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x is:

by sanju09 » Fri Apr 03, 2009 3:39 am
In the equation 2 ^ (x + 5) = 2 ^ (x + 3) + 6, the value of x is:
A. 2
B. 3
C. -4
D. 4
E. -2
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by scoobydooby » Fri Apr 03, 2009 4:02 am
2 ^ (x + 5) = 2 ^ (x + 3) + 6

=>2 ^ (x + 5)-2 ^ (x + 3)=6
=>2^(x+3){(2^2)-1}=6
=>2^(x+3)=6/3=2
equating the powers on both sides,

x+3=1
=>x=-2
hence, E