Triangle Angle Sum Theorem Missing Angles in Triangles Worksheet

Angle Sum and Exterior Angles of Triangles, Parallel Lines and Transversals Bundle

Three worksheets on the following topics: * Triangle Angle Sum Theorem * Exterior Angles of a Triangle * Parallel Lines and Transversals The first worksheet has exercises that aim to to strengthen your students’ skill at finding an unknown angle measure in a triangle, using the triangle angle sum theorem. Using the fact that the sum of the three interior angles of any triangle is 180 degrees, students set up equations and solve for the missing angles. There are 16 problems that vary in level of difficulty. In the first questions students are given a triangle and two of the angle measures, and have to find the missing third angle measure. In the next problems students are given some special types of triangles (right-angled, equilateral and isosceles) and all the required information to set up an equation and solve to find a missing angle. In the last problems, they are given composite shapes consisting of two or more triangles and in order to find the required missing angle they first have to find some other angles. The second worksheet is on the exterior angles of a triangle. The exercises require to use the fact that an exterior angle of a triangle is equal to the sum of the two interior opposite angles. The third worksheet is on angle relationships of angles formed when two lines are cut by a transversal. The following relationships are included: corresponding angles, alternate interior angles, consecutive interior angles, vertical angles and supplementary angles. Introductory and more advanced problems are included. Students practice finding the value of missing angle measures using the angle relationships seen in parallel lines cut by a transversal to form equations and then solve. Detailed solutions are provided.