EngageNY
Perimeter and Area of Triangles in the Cartesian Plane
Pupils figure out how to be resourceful when tasked with finding the area of a triangle knowing nothing but its endpoints. Beginning by exploring and decomposing a triangle, learners find the perimeter and area of a triangle. They...
Mathed Up!
Area of Compound Shapes
Scholars learn how to determine the area of compound shapes by finding the areas of the basic shapes that make it up. Pupils find the areas by adding areas together or subtracting them.
Curated OER
Triangle Area by OnlineMathLearning.com
For this online math worksheet, middle schoolers practice finding the area of triangles, given their outside dimensions. When complete, students submit their answers and get instant feedback regarding their accuracy.
Illustrative Mathematics
Area of a Trapezoid
Here is a straightforward example of how to apply the Pythagorean Theorem to find an unknown side-length of a trapezoid. Commentary gives additional information on proving that the inside of the trapezoid is a rectangle, but is...
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....
Mathed Up!
Area of Sector and Length of Arcs
Viewers learn how to apply proportional reasoning to find area of sectors and arc lengths with a video that starts off explaining how to find the areas of circle sectors and the lengths of arcs. Scholars then practice solving problems...
Government of Hong Kong
Areas and Volumes - 2D Shapes
Unfortunately for young mathematicians, the world isn't made entirely of parallelograms, triangles, and trapezoids. After first learning the area formulas for these common shapes, students apply this new knowledge to...
Flipped Math
Unit 9 Review: Area of Polygons
It's time to show what you know! Individuals first review finding the area of polygons using the formulas from parallelograms to regular polygons. They then brush up on finding the area and circumference of circles, as well as reviewing...
Mathed Up!
Sine and Cosine Rules and Area of Triangles
Learners discover how to find missing sides and angles using trigonometry. Scholars first watch a video covering the Law of Sines and Cosines, as well as the area formula for a triangle. To test their knowledge, they complete a worksheet...
Curated OER
Finding the Area of an Equilateral Triangle
The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...
EngageNY
Perimeter and Area of Polygonal Regions in the Cartesian Plane
How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...
Curated OER
Perimeter and Area 5
In this calculating area worksheet, middle schoolers use their problem solving skills and the information provided to find the area of 6 triangles.
Corbett Maths
Area under a Graph
What? The calculation of area is a linear distance? A short video shows how to use the areas of simple polygons to estimate the area under a graph. Pupils divide the area under a curve into figures to easier calculate the area. Given...
Curated OER
Area of Triangle Worksheet
In this area worksheet, students find the area of a triangle given the height and the base. They also find the height or base given the area of the triangle.
Mathed Up!
Surface Area
Surface area is the sum of the parts. Given the measurements of different prisms, pupils determine their surface areas. Individuals find the area of each surface and figure out the surface area by finding the sum. The video, part of a...
Curated OER
Area of Triangle
In this area of a triangle worksheet, students solve 3 problems where they calculate the area of a triangle when they are given the length of the base and the height and the formula.
Math Mammoth
Finding the Area of Rectangles, Parallelograms, and Triangles
In this area of polygons activity, 9th graders solve two area of rectangles, one area of parallelogram, and ten area of triangles problems. The formulas for finding the area of these figures are provided.
Helping with Math
Geometry: Areas of Triangles
For this areas of triangles instructional activity, students observe given polygons. They determine the area of triangles, rectangles and compound figures. This one-page instructional activity contains 5 multi-step problems. This...
Curated OER
Coordinate Planes - Area of Triangle
In this online math worksheet, learners find the area of a variety of triangles given the measurements of their vertices. This excellent resource allows the students to check their answers, and to get "hints" should they run into...
Corbett Maths
Pythagoras Rectangles and Isosceles Triangles
When does the Pythagorean Theorem come in handy? An intriguing video uses the Pythagorean Theorem to solve problems other than simply finding the length of a side of a right triangle. Pupils find the diagonal of a rectangle and the...
Willow Tree
Surface Area of Three-Dimensional Figures
Lateral area and surface area are simple concepts, but calculating them is not as easy! Using formulas, learners calculate lateral area and surface area for the same three-dimensional figures. The resource discusses the formula variables...
Curated OER
Area of Parallelogram and Triangle
In this geometry instructional activity, 10th graders determine the area of triangles and parallelograms. The one page interactive instructional activity contains ten questions. Answers and hints are included.
Curated OER
Area of Shaded Region (rectangles and triangles)
In this online math learning exercise, students determine the area of shaded regions within rectangles and triangles. This excellent resource allows the students to check their answers, and to get "hints" should they run into...
Curated OER
Six Find the Area of Triangles Given the Vertices Problems
For this area of a triangle worksheet, students calculate the area of six triangles given the coordinate of the vertices. Grids are provided.