Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
EngageNY
Putting the Law of Cosines and the Law of Sines to Use
Use the Law of Cosines and the Law of Sines to solve problems using the sums of vectors. Pupils work on several different types of real-world problems that can be modeled using triangles with three known measurements. In the process,...
Curated OER
Trigonometric Ratios
Students measure and analyze angles. In this trigonometry lesson, students measure angles and distances use non-traditional techniques. They identify the different ratios of sine, cosine and tangent.
Curated OER
Classifying Triangles
For this classifying triangles worksheet, 10th graders solve 9 various problems that classify triangles into categories. First, they refer to the figure shown of an isosceles triangle with two line parallel. Then, students name the...
EngageNY
The Angle-Angle (AA) Criterion for Two Triangles to Be Similar
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
EngageNY
The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
Curated OER
Identify Triangles: Acute, Right, Obtuse, Straight
In this triangles worksheet, students draw angles with given measurements and identify each as either acute, right, obtuse or straight. A reference web site is given for additional activities.
Curated OER
Drawing Quadrilaterals
In this math worksheet, learners draw quadrilaterals and also find the sums of the inner angles for each. They practice drawing rhombuses as unique quadrilaterals.
Curated OER
Intro To Quadrilaterals
Students engage in a lesson plan that is concerned with the concept of quadrilaterals and how they are used to create a rectangle for a door. They create a drawing of a quadrilateral while finding the sum of the angles. They practice...
Curated OER
More Congruent Triangles
In this congruent triangles learning exercise, 10th graders solve 6 various forms of problems that include a proof and a word problem. First, they draw and label triangles and indicate the additional pairs of corresponding parts that...
Curated OER
Geometry
For this line and angles worksheet, learners explore basic geometry vocabulary. They classify polygons. Students determine the area and perimeter of given shapes. They examine the parts of a circle, find volume and surface area of...
Curated OER
Parallel Lines and Transversals
In this parallel lines and transversals worksheet, 10th graders solve nine different problems related to measuring parallel lines and transversals. First, they name two more pairs of parallel segments, two more skew segments, and two...
Curated OER
Measurement
Fifth graders measure specified distances when given perpendicular lines. In this measurement lesson plan, 5th graders draw the lines themselves.
Curated OER
Geoboard Ideas
Students build polygons on their geoboards. In this geometry lesson plan, students build and then draw it on paper and label it. Students then switch with a partner to try an make a symmetrical shape.
Curated OER
Triangles
In this triangles worksheet, students solve six word problems where they determine the angles measures in different triangles.
Curated OER
Perpendicular Bisector of a Line Segment
High Schoolers investigate the perpendicular bisector of a line segment. They use Cabri Jr. to construct the perpendicular bisector of a segment. The dynamics capabilities of Cabri Jr. allow your learners to observe the lengths of the...
Curated OER
Similar Situations
Students explore intersecting lines. In this intersecting lines activity, students investigate shapes consisting of parallel, perpendicular, and similar lines. Students investigate these lines in shapes around them.
Curated OER
Duplicating Segments and Angles
Tenth graders investigate geometric construction. In this geometry lesson, 10th graders explore the procedure for copying an angle and a segment. The lesson emphasizes the difference between a sketch, a drawing, and a construction and...
Curated OER
Drawing a Triangle with Cabri Junior
Learners draw triangles on their graphing calculators using the Cabri Junior application. In this graphing calculator lesson, students follow step by step directions to create triangles on their calculator. They identify the type of...
Curated OER
How are Trig Ratios Used to Measure Triangle Sides
Students identify the ratios of trig identities. In this geometry lesson, students solve the missing sides and angles of triangles using trig ratios. They relate the graphs and waves to real life scenarios.
Inside Mathematics
Rhombuses
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
Illustrative Mathematics
Regular Tessellations of the Plane
Bringing together the young artists and the young organizers in your class, this lesson takes that popular topic of tessellations and gives it algebraic roots. After covering a few basic properties and definitions, learners attack the...
Curated OER
Polygon Sum Conjecture
In this geometry worksheet, 10th graders identify the missing angles using the polygons sum conjecture. They measure exterior and interior angles using their angle theorems. There are 63 problems.
Curated OER
Identify the Shape
10 this geometry worksheet, students identify the different angles created by polygons and name the shape created based on the number of sides. There is an answer key.