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...

Do your learners always, sometimes, or never remember the properties of the segments in triangles? Get that number closer to always with a creative lesson analyzing all four segments. Scholars consider a statement about one of the...

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...

For this geometry worksheet, young scholars differentiate between regular triangles and isosceles triangles. They apply the converse theorem and the vertex angle. There are eleven questions with an answer key.

Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...

This is a good model for learners to visualize triangles of the same base and height. They can can begin to comprehend that these triangles will have the same area no matter how the triangle is drawn. It is part of a series of resources...

In this triangles worksheet, 10th graders solve 3 extensive informal geometry problems that involve triangles. First, they sketch a triangle, selecting 3 of the sides and constructing 3 midpoints. Students then draw each of 3 medians by...

Prove the Law of Sines two ways. The ninth segment in a series of 16 introduces the Law of Sines to help the class find lengths of sides in oblique triangles. Pupils develop a proof of the Law of Sines by drawing an altitude and a second...

In this right triangles worksheet, 10th graders solve and complete 13 different problems. First, they find the lengths of both missing sides. Then, students find the altitude of an equilateral triangle given the measure of one side. They...

For this triangles worksheet, 10th graders solve and complete 6 various types of problems. First, they draw a median and the altitude from the given angle in each triangle illustrated. Then, students determine which angle is equidistant...

In this triangles activity, students identify the median, altitude, segment, angle bisector, perpendicular bisector and triangle midsegment of triangles.  They find the perimeter of triangles.  This three-page activity...

In this triangle worksheet, high schoolers solve 1 word problem about the lengths of a triangle. Students determine the length of the longest side given the ratio of the angle measures.

In this triangles worksheet, students identify the parts of a triangle.  They determine the value of an angle measurement, and identify the characteristics of triangles.  This two-page worksheet contains 10 problems.  This...

In this right triangles worksheet, 10th graders solve and complete 12 various types of problems. First, they solve for x given each of the right triangles shown. Then, students determine the length of the shorter diagonal given the...

In this geometry instructional activity, students solve both kinds of special right triangles. There are 12 questions with multiple parts.

For this geometry worksheet, 10th graders determine if a given segment is a median or altitude of a triangle and use then find the indicated missing length or equation of a line.  The two page worksheet contains twenty...

In this geometry worksheet, 10th graders review the vocabulary associated with the special segments of a triangle and the associated points of concurrency and solve problems in which they find the indicated missing angle or...

In this special segments in triangles worksheet, 10th graders solve 5 different types of triangles. First, they identify and describe the four types of segments associated with triangles. Then, students draw and label a figure that...

For this vocabulary worksheet, students match a given vocabulary word to the correct definition.  Words include such terms as altitude, centroid, circumcenter, circumscribed circle, inscribed circle, median and...

In this special segments in triangles worksheet, 10th graders solve 6 various types of problems related to determining types of segments found in triangles. First, they find a segment if the line parallel is a median or an altitude....

For this triangles worksheet, 10th graders solve and complete 2 different problems. First, they find the perimeter of each triangle as described. Then, students find the slope of each side and altitude to each side of the triangles. In...

For this special right triangles worksheet, 10th graders solve 9 different problems related to measuring various types of right triangles. First, they find the values of x and y in each right triangle shown. Then, students find the...

In this parts of similar triangles worksheet, 10th graders solve 6 different problems related to determining the value of various parts of similar triangles. First, they find the value of x in the 2 figures shown. Then, students find the...

In this right triangles worksheet, 10th graders solve 10 different problems that include determining the means proportionally in each right triangle. First, they use the given information to determine the measure of each line segment....