If the line with equation y=−2x+7 is rotated 90° clockwise about the origin, what are the

coordinates of the image of its y-intercept?

A. (0,−7)
B. (−7,0)
C. (2,0)
D. (7,0)

Respuesta :

frika

First, find the y-intercept of the line y=-2x+7. When x=0 you have that y=-2·0+7, y=7, then point (0,7) is the y-intercept.

When you rotate this line 90° clockwise about the origin, then point (0,7) will be placed on the x-axis in positive x-direction. Rotation preserves the distances, then the coordinates of the image are (7,0).

Answer: correct choice is D.