Question

When point E (-9, 3) is rotated 180� about the origin, its coordinate becomes (3, 9).
True
False

Answer 1

false (-9, -3)

Answer 2

thanks hun!

Answer 3

your welcome

Answer 4

how do you know its -9 -3?

Answer 5

If you substitute the rotation matrix for 180 degrees, you'd get the rule
T180(x,y)=(-x,-y), so the rotated point should be (9,-3)

Answer 6

^know that, or you become a lazy slob like me who imagined it on the coordinate plane instead of remembering the rule. (Facepalm)

Answer 7

You have a point. But to help someone, we need something concrete to work on.

Answer 8

thanks everyone!

Answer 9

I see nothing wrong with imagining it on a coordinate plane. The rule makes more since that way.

Answer 10

sense*