CPALMS
Cpalms: How Many Trees?
[Free Registration/Login Required] In this formative assessment task, students are asked to find the density and the estimated number of trees in a forest, given certain parameters. Samples of student responses and possible...
Wolfram Research
Wolfram Math World: Vector Difference
This site defines vector difference. Includes a formula and links to related topics.
National Council of Teachers of Mathematics
The Math Forum: Vector Addition: Algebra
Illustration and description of how to add vectors using algebra.
Washington State University
Washington State University: Math 101: Rational Exponents: Rules
A list of rules for how to convert from radical to exponential form and from exponential to radical form.
Math Words
Mathwords: Inscribed Circles
Mathwords provides an explanation and a diagram of an inscribed circle. By clicking on any of the highlighted words, you will learn about related terms.
Sophia Learning
Sophia: Finding the Area of a Sector Using the Central Angle: Lesson 2
This lesson explains how the central angle can be used to determine the area of a sector and presents several practice problems. Includes answers and a short quiz. It is 2 of 5 in the series titled "Finding the Area of a Sector Using the...
Sophia Learning
Sophia: Finding the Equation for an Ellipse: Lesson 2
This lesson explains the steps for how to find the equation for an ellipse given its foci and vertices. It is 2 of 4 in the series titled "Finding The Equation For An Ellipse."
Sophia Learning
Sophia: Finding the Equation for an Ellipse: Lesson 1
This brief lesson shows how to find the equation for an ellipse given its foci and vertices and presents a problem to try. Includes a short quiz. It is 1 of 4 in the series titled "Finding The Equation For An Ellipse."
Sophia Learning
Sophia: Scalar Multiplication: Lesson 3
This brief lesson will introduce scalars, and demonstrate how to perform scalar multiplication with matrices. It is 3 of 10 in the series titled "Scalar Multiplication."
Sophia Learning
Sophia: Triangle Congruence Theorem (Hl): Lesson 5
This lesson will present the Hypotenuse-Leg Triangle Congruence Theorem. It is 5 of 5 in the series titled "Triangle Congruence Theorem (HL)."
Sophia Learning
Sophia: Using Matrices to Organize Data: Lesson 2
This lesson provides real-world examples that demonstrate how to organize data into matrices. It is 2 of 5 in the series titled "Using Matrices to Organize Data."
Sophia Learning
Sophia: Using Matrices to Organize Data: Lesson 1
This lesson provides some real-world examples that demonstrate how to organize data into matrices. It is 1 of 5 in the series titled "Using Matrices to Organize Data."
Sophia Learning
Sophia: Scalar Multiplication: Lesson 1
This brief lesson will introduce scalars, and demonstrate how to perform scalar multiplication with matrices. It is 1 of 10 in the series titled "Scalar Multiplication."
Free Math Help
Free Math Help: Special Parallelograms: Squares, Rectangles, and Rhombuses!
Examines special parallelograms. Students learn about a rectangle, rhombus, and square. Definitions and examples with solutions are included.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Rational Exponents
Find a quick, concise explanation of rational exponents. Examples are given and clearly explained.
ClassFlow
Class Flow: Congruence in Triangles
[Free Registration/Login Required] This lesson helps teach congrence in triangles. Includes practice with postulates, theorems, and logical reasoning.
Math Is Fun
Math Is Fun: Constructing a Triangle With 3 Known Sides
Students learn how to construct a triangle with three known sides using a straightedge and a compass. Includes an animated demonstration.
Free Math Help
Free Math Help: Completing the Square in Circle Equations
This discussion examines how to complete the square in circle equations. Students learn about the math concept through definitions and examples with detailed solutions.
Sophia Learning
Sophia: Triangle Proportionality Theorem: Lesson 4
This lesson presents how to apply the triangle proportionality theorem to solve for unknown variables and side lengths. It is 4 of 6 in the series titled "Triangle Proportionality Theorem."
Wolfram Research
Wolfram Math World: Math World: Geometric Similarity: Similar
A definition for similar figures, directly similar, and inversely similar figures in Mathematics. Provides pictures to aid understanding.
Windstream
Ojk's Precalculus Study Page: Parabolas
Good study tutorial about parabolas. There are examples of finding the equation of the parabola or the focal point and directrix that students can examine and attempt.
ClassFlow
Class Flow: Goats and Monsters
[Free Registration/Login Required] Students explore methods to measure lengths of squares and radius of a circle in trying to keep a goat from escaping.
Shmoop University
Shmoop: High School: Number and Quantity: Quantities Hsn q.a.3
Standard HSN-Q.A.3 states: "Choose a level of accuracy appropriate to limitations on measurement when reporting quantities." This page explains what this standard means. Click on 'Sample Assignments' for some quick drills.
Jim Loy
Jim Loy's Mathematics Page: Congruence of Triangles
Find explanations of the ways to prove triangles are congruent. There is a link for Congruence Of Triangles, Part II to find the proofs of some ways to prove congruence of triangles from other postulates (i.e. Assume SAS prove ASA).