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The Division of Polynomials
Build a true understanding of division of polynomials. Learners use their knowledge of multiplying polynomials to create an algorithm to divide polynomials. The area model of multiplication becomes the reverse tabular method of division.
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Multiplying and Dividing Rational Expressions
Five out of four people have trouble with fractions! After comparing simplifying fractions to simplifying rational expressions, pupils use the same principles to multiply and divide rational expressions.
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The Geometric Effect of Multiplying by a Reciprocal
Class members perform complex operations on a plane in the 17th segment in the 32-part series. Learners first verify that multiplication by the reciprocal does the same geometrically as it does algebraically. The class then circles back...
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Dividing by (x – a) and (x + a)
Patterns in math emerge from seemingly random places. Learners explore the patterns for factoring the sum and differences of perfect roots. Analyzing these patterns helps young mathematicians develop the polynomial identities.
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Directed Line Segments and Vectors
Investigate the components of vectors and vector addition through geometric representations. Pupils learn the parallelogram rule for adding vectors and demonstrate their understanding graphically. They utilize the correct notation and...
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The Relationship Between Visual Fraction Models and Equations
Ours is to wonder why, not just to invert and multiply. The seventh installment of a 21-part module uses fraction models to help pupils understand why the invert-and-multiply strategy for dividing fractions works. They then work on some...
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Substituting to Evaluate Addition and Subtraction Expressions
Substitute this resource for what you used to use. Learners identify patterns in data tables and write addition and subtraction expressions to represent relationships. Substitution allows them to solve problems in context in the 20th...
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Linear Functions and Proportionality
Connect linear equations, proportionality, and constant rates of change to linear functions. Young mathematicians learn how linear equations of the form y = mx + b can represent linear functions. They then explore examples of linear...
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Matrix Multiplication Is Not Commutative
Should matrices be allowed to commute when they are being multiplied? Learners analyze this question to determine if the commutative property applies to matrices. They connect their exploration to transformations, vectors, and complex...
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Estimating Centers and Interpreting the Mean as a Balance Point
How do you balance a set of data? Using a ruler and some coins, learners determine whether the balance point is always in the middle. Through class and small group discussions, they find that the mean is the the best estimate of the...
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Making Scale Drawings Using the Parallel Method
How many ways can you create a dilation? Many! Individuals strengthen their understanding of dilations by using various methods to create them. The new technique builds on pupils' understanding of the ratio method. Using the ratio,...
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Using Trigonometry to Find Side Lengths of an Acute Triangle
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
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What Is Area?
What if I can no longer justify area by counting squares? Lead a class discussion to find the area of a rectangular region with irrational side lengths. The class continues on with the idea of lower approximations and...
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Parallel and Perpendicular Lines
Use what you know about parallel and perpendicular lines to write equations! Learners take an equation of a line and write an equation of a line that is parallel or perpendicular using slope criteria. They then solve problems to...
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Ferris Wheels—Tracking the Height of a Passenger Car
Watch your pupils go round and round as they explore periodic behavior. Learners graph the height of a Ferris wheel over time. They repeat the process with Ferris wheels of different diameters.
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Overcoming Obstacles in Factoring
What do you do when factoring doesn't work? Learners complete the square when faced with quadratic expression that don't factor traditionally. They then use factoring by grouping to solve polynomial equations.
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Equivalent Rational Expressions
Rational expressions are just fancy fractions! Pupils apply fractions concepts to rational expressions. They find equivalent expressions by simplifying rational expressions using factoring. They include limits to the domain of the...
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Solving Rational Equations
What do fractions and rational expressions have in common? Everything! Learners use common denominators to solve rational equations. Problems advance from simple to more complex, allowing pupils to fully understand the material before...
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Linear Systems in Three Variables
Put all that algebra learning to use! Using algebraic strategies, learners solve three-variable systems. They then use the three-variable systems to write a quadratic equation given three points on the parabola.
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Are All Parabolas Similar?
Congruence and similarity apply to functions as well as polygons. Learners examine the effects of transformations on the shape of parabolas. They determine the transformation(s) that produce similar and congruent functions.
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Extending the Domain of Sine and Cosine to All Real Numbers
Round and round we go! Pupils use reference angles to evaluate common sine and cosine values of angles greater than 360 degrees. Once they have mastered the reference angle, learners repeat the process with negative angles.
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Graphing the Sine and Cosine Functions
Doing is more effective than watching. Learners use spaghetti to discover the relationship between the unit circle and the graph of the sine and cosine functions. As they measure lengths on the unit circle and transfer them to a...
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Basic Trigonometric Identities from Graphs
Have young mathematicians create new identities! They explore the even/odd, cofunction, and periodicity identities through an analysis of tables and graph. Next, learners discover the relationships while strengthening their...
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Trigonometric Identity Proofs
Proving a trig identity might just be easier than proving your own identity at the airport. Learners first investigate a table of values to determine and prove the addition formulas for sine and cosine. They then use this result to...