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Geometry 10.2 Set III #4

Kerry wrote:
For Ch. 10, Lesson 2, Set III number 4 asks for rectangles with a ratio of 3/4.  The key says there are 4 rectangles that have dimensions of 1.5×2.  ABHG is correct, but the other three rectangles seem to be wrong.  The key lists BDJI (which doesn’t even make a rectangle), CEKI (which is a 1.5×3 rectangle), and DFLJ (which is also a 1.5×3 rectangle). Can you confirm the correct rectangles are ABHG, CDJI, and EFLK? I know it seems obvious, but just want to make sure I’m not missing something here.
Dr. Callahan Wrote:
You are correct. This looks like a typo. The original solutions manual (titled “Enhanced Teacher’s Guide for Geometry – ISBN: 978-0716756071) had it correct. I have noticed a few places that the answers in the newer solutions manual have typos.
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Geometry Ch5.1 #46

Question from Kerry:

The answer key gives 5 statement answers, but the proof only has 4 statements.  I don’t know which of the 5 in the answer key is extraneous.  Assuming the last one should be dropped, the answer in the key for statement 2 is subtraction, but I think it is addition.  There is no subtraction for statement 2.  Could you clarify/verify the 4 correct reasons for the 4 steps?

 

Answer from Dr. Callahan:

This should be
1) Given2) Addition3) Given4) Substitution
The answer key you have is a reprint from the original (oddly the original has the correct answers) and is new. We will document any errors at askdrcallahan.com/support.