Question

which of the lines below is a line of symmetry? a. neither b. both c. yellow d. red

Explanation:

Step1: Recall the definition of line of symmetry

A line of symmetry divides a figure into two congruent (identical) parts such that when the figure is folded along the line of symmetry, the two parts match exactly.

Step2: Analyze the red line

For an isosceles triangle (assuming the given triangle is isosceles as per the line shown), the vertical line (red line in the problem - which is the altitude, median and angle - bisector for an isosceles triangle) divides the triangle into two congruent right - angled triangles. When folded along this red line, the two halves of the triangle will overlap perfectly.

Step3: Analyze the other (yellow) line

The non - vertical (yellow) line does not divide the triangle into two congruent parts. If we were to fold the triangle along the non - vertical line, the two parts of the triangle would not match.

Answer:

D. Red