SOLUTION: log(y – x) = 0 and 2log y = log(21 + x)

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Question 837857: log(y – x) = 0 and 2log y = log(21 + x)
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
log(y – x) = 0 and 2log y = log(21 + x)
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log(y-x)=0
10^0=y-x
y-x=1
y=1+x
..
2log(y)=log(21+x)
log(y^2)=log(21+x)
y^2=21+x
(1+x)^2=21+x
1+2x+x^2=21+x
x^2+x-20=0
(x+5)(x-4)=0
..
x=-5(reject,y>0)
y=-4(reject,y>0)
or
x=4
y=5