by DaleCallahan | Jul 27, 2019 | Algebra, Algebra Chapter 16, Errors, Known Algebra Errors
This is an error in the book by Master Books (ISBN: 978-0890519851) – the book with the blue cover showing the world. The problem is discussing hens and rabbits with a total of 30 heads and 86 feet. ERROR: The solution manual is referring to the wrong problem...
by DaleCallahan | Jun 7, 2019 | Algebra, Algebra Chapter 13
Question from Grace: We are using this test A as a practice test. We can’t figure out how to solve this. Answer from Dr. Callahan: Grace, To solve this one, you take the square root of each side +/- SQRT ( 16x^2 + 8x +1 ) = +/- SQRT (9) The left side needs a...
by DaleCallahan | Jun 4, 2019 | Algebra, Algebra Chapter 10
Error in Solutions Manual The Solutions Manual has the answer from the older version of the book (which used a flag of 104 x 235. Flags have grown since then. 😉) Just FYI – the older flag was flown in Detroit on the side of the J.L. Hudson Store – which no...
by DaleCallahan | May 23, 2019 | Geometry, Geometry Chapter 11, Geometry Tests
Question from Anya Course: Geometry Chapter/Lesson/Problem11 test7b Issue: I’m supposed to find Angle APM. To find the angle, I used tan APM=20/70, which gives 15.9 degrees. The solutions manual used sin APM=20/70, which gives 16.6 degrees. Sine is...
by DaleCallahan | May 3, 2019 | Algebra, Algebra Chapter 5
Ch5.6 #15 As before – all are similar so I will pick the harder one. Givens AB = CD AB = 9(x-2) CD = x + 3(x+5) Therefore, 9(x-2) = x + 3(x+5) Now multiply out and solve 9x – 18 = x + 3x + 15 9x – x – 3x = 15 + 18 5x = 33 x = 6.6 Now go back and find the...
by DaleCallahan | May 3, 2019 | Algebra, Algebra Chapter 5
Now let’s look at Ch 5.6 #14. Parts a-c are similar – so will do part c since the harder. Area = x + 20 = (x-1)4 > I am just stating all things that are equal based on the given. x+20 = (x-1)4 x+20 = 4x -4 > multiplied out 20 + 4 = 4x – x > moved similar...
by DaleCallahan | May 3, 2019 | Algebra, Algebra Chapter 5
For problem 5.6, parts a-d are all pretty much the same. Here I will do part d) since a hair more complex. The steps the same for the others. Since AB = CD, we can substitute the following AB is x + 6(x+2) CD is 2(x+10) To get x + 6(x+2) = 2(x+10) So to find the...
by DaleCallahan | Apr 23, 2019 | Geometry, Geometry Chapter 14
Question from Joy: We are in Geometry 3 rd edition. Chapter 14 lesson 2 number 22-23. Page 582. How do you get 108? The answer in key says 3 x 180/5? Why? I think I missed something important yet simple. I was thinking divide 360/5. What an I doing wrong? Thanks!...
