SOLUTION: Solve and check a) 2log(x-1) = 2+ log 100

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Question 742189: Solve and check
a) 2log(x-1) = 2+ log 100
Found 2 solutions by josgarithmetic, lwsshak3:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
2*log(x-1)=2+log(100)
2log(x-1)-log(100)=2
log(x-1)^2-log(100)=2
log((1/100)(x-1)^2)=2

What you do next depends on what the base is. Assuming you are using some base, b, you would transform:
b%5E2=%281%2F100%29%2A%28x-1%29%5E2
Also, looking carefully at the factor on the right side,
b%5E2=%28%28x-1%29%2F10%29%5E2
Seeing that, the base must be equal to the expression shown in the same position on the rightside:
b=%28x-1%29%2F10.

From this, 10b=x-1
highlight%28x=10b%2B1%29 You need to know the value of b in order to find anything further.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve and check
a) 2log(x-1) = 2+ log 100
2log(x-1) = 2+2
2log(x-1) = 4
log(x-1) =2=log100
x-1=100)
x=101
check:
2log(x-1)=2log(100)=2*2=4
2+log 100=2+2=4