Posted by Sheenybeany on Thursday, July 31, 2014 at 6:04pm.
Point Q is the image of point P under a dilation with center O and scale factor 4. If PQ = 18, then what is OP?

Translations  Steve, Thursday, July 31, 2014 at 7:03pm
all distances also scale by a factor of 4.

Translations  Sheenybeany, Thursday, July 31, 2014 at 7:18pm
Sorry, but that's not right :(
I really need to do this. Any help? 
Translations  Steve, Friday, August 1, 2014 at 6:04am
what do you mean by "that's not right?" What calculation did you do?
Without loss of generality, we can take the distances to be measured along the xaxis.
We have two points, P and Q on the xaxis, where
OQ = 4(OP) because of the dilation.
Since PQ=18, that means that 3/4 of the distance OQ = 18.
So, OQ = 24 and OP = 6.
All because the distances grew by a factor of 4, as I said. 
Translations  Sheenybeany, Friday, August 1, 2014 at 12:34pm
Like I said, the answer is wrong! I put it into my online class and it said it was 6. Thanks a whole bunch, Steve.