EngageNY
An Area Formula for Triangles
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
Buffalo State
A Five Day Approach to Using Technology and Manipulatives to Explore Area and Perimeter
Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of...
Del Mar College
Formulas for Elementary and Intermediate Algebra
Give your scholars the support they need to work with formulas. A reference page offers definitions and picture examples of perimeter, area, surface area, volume, the Pythagorean theorem, a variety of shapes, and more.
EngageNY
Replacing Letters with Numbers
When did letters become the same as numbers? Scholars learn about substituting numbers for letters to evaluate algebraic expressions in the seventh part in a series of 36. The lesson focuses on expressions related to geometry, such as...
National Security Agency
It's Probably Probable
Learners make predictions and draw conclusions from given information as they learn the meaning of probability in this vocabulary-rich, integrated activity that presents a variety of teaching strategies to motivate and reach...
West Contra Costa Unified School District
Solving and Using Literal Equations
You literally need to use the resource. Young mathematicians solve geometric problems by using literal equations. They go on to solve distance/rate/time problems by using literal equations — a great progression that helps introduce the...
West Contra Costa Unified School District
Polynomial Division
Multiply the ways your scholars can find the quotient with polynomial division. A lesson introduces polynomial division via long division, synthetic division, generic area model, and using the definition of division. Learners then...
Teach Engineering
Graphing Equations on the Cartesian Plane: Slope
Slopes are not just for skiing. Instructors introduce class members to the concept of slope and teach them how to calculate the slope from a graph or from points. The lesson also includes the discussion of slopes of parallel and...