Thursday, November 17, 2011

STEM Friday: Mystery Math: A First Book of Algebra

Mystery Math: A First Book of Algebra
written by David A. Adler; illustrated by Edward Miller
2011 (Holiday House)
Source: Orange County Public Library

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David A. Adler and Edward Miller have done it again! Last year they created the terrific Time Zones which translated a complex subject into a fun read. As if that wasn't difficult enough, this dynamic duo is now tackling algebra in Mystery Math. A haunted house is the perfect setting for a subject that strikes fear in the hearts of millions. Adler starts the book by comparing equations to seesaws. Both need to be balanced in order to work. Simple equations (e.g. 6 + 2 = 8) combined with spooky owls on tree branches illustrate this idea of balance. Next, the mystery number is introduced. Adler explains that variables get their name because they vary from one equation to the next. A simple rule is given to help deal with variables: Whatever is done to one side of the equal sign must be done to the other side. Finally, readers are guided on how to solve for variables in each of the four operations (addition, subtraction, multiplication, and division). In each section, guides Mandy and Billy and caretaker Igor present the operation in the form of an algebraic word problem. The problem is broken down so the reader can see how to find the value of the variable. A nice finishing touch is a piece of procedural text in the back matter that shows you how to build a balance scale that can be used to find unknown numbers in equations.

Mystery Math would be a great introduction for elementary students who are beginning to learn about algebra. Students could write their own word problems to match the setting of the book and share these for homework.

Other reviews:
Nonfiction Detectives


  1. Solve this 4x4 matrix using Cramer's rule
    (1-a1-a2 ; a1 ; a2 ; 0)
    (b1 ; 1-b1-a2+c2 ; 0 ; a2-c2)
    (b2 ; 0 ; 1-b2-a1+c2 ; a1-c1)
    (0 ; b2+c2 ; b1+c1 ; 1-b1-c1-b2-c2)

    all 4 rows equal zero and the variables to be found (going across the rows) are w, x, y and z.

    When I tried to solve the first determinant I got 4 brackets with 3, 4, 4 and 5 elements in and the multiplying out got too confusing so I am not sure if it was right or not.

    My teacher said Cramer's rule is the easiest way to solve so I want to do it by this method but I've never been taught it and I can't find an example using algebra.

    if there is any post regarding Algebraic equations so please give me i wil post there my problem...but if you dont mind then please help me...!..

  2. Thank you for visiting, Nick! I will have to look up Cramer's rule. If you like math, check out today's post on Wonderopolis. It is about the number googol.