Answer:
Show that the slope of line SQ is 1, and the slope of line PR is -1.
Explanation:
To show that the diagonals of a square are perpendicular, Talia should demonstrate that the slope of one diagonal is the negative reciprocal of the slope of the other diagonal. Therefore, the correct sentence is:
"Show that the slope of line SQ is 1, and the slope of line PR is -1."
In a square, the diagonals are perpendicular, which means that their slopes are negative reciprocals of each other. This property is a key characteristic of squares, and it's commonly used to prove their diagonals' perpendicularity.