Consider both an even and an odd measure for the vertex angle.
Sometimes
Practice makes perfect
Consider the given statement.
If the measure of the vertex angle of an isosceles triangle is an integer, then the measure of each base angle is an integer.
We want to determine when this statement is true. To do so, let's draw four isosceles triangles with vertex angles of 80, 85, 90, and 95, and examine their base angles.
Looking at the triangles, it seems that the measure of each base angle is an integer only if the measure of the vertex angle is an even integer. Therefore, the statement is sometimes true.
Extra
Isosceles Triangle
An isosceles triangle is a triangle that has two congruent sides called legs. The angle between these two sides is called the vertex angle and its opposite side is called the base. The angles formed by the legs and the base are called base angles. Base angles are congruent.
More information about isosceles triangles can be found on the following pages.
