Final answer:
An isosceles triangle, which has two sides of equal length and one line of symmetry, is an example of a triangle with only one reflection symmetry. It is characterized by a line of symmetry perpendicular to the base, dividing it into two congruent halves.
Step-by-step explanation:
To draw a picture of a triangle that has only one reflection symmetry, you need to consider an isosceles triangle. An isosceles triangle has two sides of equal length and the angles opposite those sides are equal. Due to these equal sides and angles, an isosceles triangle has a single line of symmetry, which is perpendicular to the base and bisects the vertex angle. This type of symmetry is where one-half of the triangle is a mirror image of the other half. When drawing this triangle, ensure that two sides are of the same length and the base is of different length to represent the reflection symmetry properly.
To further understand this concept, imagine a figure on a plane, with three internal angles that add up to 180 degrees, which is a characteristic of all triangles. The reflection symmetry in triangles can be observed by folding the shape along the line of symmetry and noticing that both halves align perfectly. In the case of the isosceles triangle, only one such fold is possible, resulting in one reflection symmetry.