Question 681425: log2(x+5)=log4(7x+1) solve for X
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! log2(x+5)=log4(7x+1) solve for X
convert to log base2
log2(x+5)=log2(7x+1)/log2(4)
log2(4)=2
log2(x+5)=log2(7x+1)/2
2log2(x+5)=log2(7x+1)
log2[(x+5)^2]=log2(7x+1)
(x+5)^2=7x+1
x^2+10x+25=7x+1
x^2+3x+24=0
a=1, b=3, c=24
discriminant:
b^2-4ac=9-4*1*24<0
therefore, no real solution
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