How are you supposed to rotate a triangle 270 degrees around the origin?
try redrawing the triangle
using the negative y-axis for the original x-axis, and the x-axis for the original y-axis
The easiest way is to turn the coordinate plane 270 CCW (I’m assuming it’s counter clock wise because the angle is positive), this would be the equivalent of turning you paper 3 times to the left ( or one to the right). Then count how many units and in what direction you must go in order to reach the vertex. Return your paper to its original state, and just follow the path that you counted. For example if I had a point like (5,3) and I wanted to rotate it 270 degrees around the origin. I would rotate the paper 270 and count from the origin, it would be 5 units down and 3 to the right. Once I knew this, I just put my paper back in its original state and from the origin, go 5 units down and 3 right, and I would have rotated the point 270 degrees.