geometry strategy guide page 57 ; problem set #5

[gmatxyz]

the question says at which point does the following line intersect the y axis.

if x=y/80, then how is the answer (-20,0)?
isn't the answer just (0,0)?

[RonPurewal]

i looked at page 57 of each of the 2 most recent editions of the guide (5th and 6th editions). there is nothing like this on that page of either book.
how old is the guide you're using? (if it's older than the 5th edition, i have no access to it anymore.)

in any case, the first thing you should do is double-check the problem, to make sure you've transcribed it correctly.

[gmatxyz]

its the newest edition of the strategy guide online

[RonPurewal]

ok. do you think you could attach a screen shot of the problem?
either embed it directly, or upload it to an image hosting site (such as postimage.org) and then put a link here.

...because, if that's what is actually there, then it's REALLY messed up.
not only is that internally inconsistent (as you've already noticed), but, also, the point (–20, 0) is on the wrong axis!
that point is on the x-axis, not on the y-axis.

a screenshot would go a long way toward helping resolve this issue. thanks.

[gmatxyz]

http://s22.postimg.org/m8k3dactd/image1.jpg
http://s22.postimg.org/dc9b9cm75/image2.jpg

[RonPurewal]

ok, here's what the problem is supposed to say:
http://postimg.org/image/ndf91bopf/

that should resolve the issue.

[RonPurewal]

there's also another problem: the second half of that explanation is actually the second half of the explanation for a totally different problem (namely #8 in the same set).

you'll notice that the explanation of #8 abruptly cuts off in the middle (the problem isn't finished, but the explanation stops)...
...because the second half migrated to #5.

interestingly, it seems that this happened in both the e-book and the printed book.

this error has been noted here:
http://www.manhattanprep.com/gmat/errat ... metry-6ed/

on the other hand, i don't see the error you've noted there, so i'll alert the relevant people. thanks.

[StaceyKoprince]

Thanks, gmatxyz and Ron. This is correct in the print book (ie, the print book has what Ron gave you) but not in the e-book. I'll alert the publishing team and we'll get that fixed up!

[RonPurewal]

... although the print book still has the issue in the answer key (in which half the solution to one problem has accidentally been transposed to the following page).

[HillaryD715]

Hi,

Just wanted to note that this error is still in the digital edition I purchased in September. I thought I was going crazy! Thank you for posting the errata page!

-Hillary

[Sage Pearce-Higgins]

Sorry about that.