Rotate the triangle
counterclockwise ( ) about the origin. Name the coordinates of the vertices of .
Use the eTool to complete the transformation. Notice how the points have changed. Pay attention closely to point
Notice that the
-coordinate has been multiplied by and the - and -coordinates are interchanged.
across the -axis. Name the coordinates of the vertices of .
Use the eTool. Notice how the coordinates compare to the coordinates of
. What happens to the points when you reflect across the -axis? , ,
What is the area of
What is the length of the base,
? What is the height from point to base ? Use the area formula for triangles.
Use the eTool below to solve the problem.
Click the link at right for the full version of the eTool: 6-139 HW eTool