Finding the Reflection Line On a coordinate plane, triangle 1 is reflected across the x-axis to form triangle 4, is reflected across a diagonal to form triangle 3, is reflected across the y-axis to form triangle 2. Use the figure to complete the statements. Triangle 1 is the image of triangle 2 reflected over the . Triangle 2 is the image of triangle 3 reflected over the . Reflecting triangle 4 over the y-axis results in triangle .