Hi there! Reflections across the line y = -x always go by the rule (-y, -x). We can use this rule to get our answer here. We are given the aftermath of the reflection coordinates, which are <span>A'(-1, 1), B'(-2, -1), and C'(-1, 0). All we have to do now is switch up the coordinate values and multiply them by -1. Here is the work - A'(-1, 1) => (1, -1) => x -1 => A(-1, 1) B'(-2, -1) => (-1, -2) => x -1 => B(1, 2) C'(-1, 0) => (0, -1) => x -1 => C(0, 1) Therefore, the coordinates of Triangle ABC are A(-1, 1); B(1, 2); C(0,1). Hope this helped and have a phenomenal day!</span>