Question

URGENT PLEASE HELP!!! I WILL GIVE FAN AND MEDAL!!!

If the following figure is rotated 90° counterclockwise about the origin, what is the new location?

https://lss.brainhoney.com/Resource/12429862,B6,38,1F,0/Assets/images/TransUnitExam90.jpg

A. J’ (-8, 2), K’ (-3, 0), L’ (-6, -3)

B. J’ (-2, 8), K’ (0, 3), L’ (3, 6)

C. J’ (8, -2), K’ (3, 0), L’ (6, 3)

D. J’ (2, 8), K’ (0, -3), L’ (-3, 6)

Answer 1

@mathmale

Answer 2

Its B right?

Answer 3

Have you done this kind of problem before? If so, have you done it graphically, or using trigonometry? Which course are you in? Sorry, Vera, but I don't respond to "its B right?" questions unless you explain and show your method of arriving at this possible answer.

Answer 4

Well I asked someone and they said it was B but the didn't show me how they got their answer. That's why I'm confused. @mathmale

Answer 5

@mathmale

Answer 6

Regardless, Vera, it's you who needs to do the problem, show you work, and so on, so that later on when you see this kind of problem, you'll be able to do it yourself. In this case I really don't even want to know what somebody else said.

Have you done this kind of problem before? If so, have you done it graphically, or using trigonometry? Which course are you in?

Answer 7

I have done a problem like this before. I used trig I think. I multiplied the x coordinates by-1 and I am in Honors Geometry (9th grade)

Answer 8

Consider point K alone. What are its coordinates now? We're going to rotate point K about the origin, counterclockwise, 90 degrees. Where will you end up? Give the coordinates of K'.

Answer 9

coordinates of K are (0,3) what would i do to the coordinates for the final rotations points?

Answer 10

We're going to rotate point K about the origin, counterclockwise, 90 degrees. Where will you end up? Give the coordinates of K'.

Answer 11

i'm not sure where it would be. that's why im asking this question...

Answer 12

What does "counterclockwise" mean?

Answer 13

um the opposite direction of clockwise

Answer 14

Not trying to be funny: but what does "clockwise" mean?

Answer 15

moving from right to left in a circle

Answer 16

"right" direction? Actually, Vera, "clockwise" moves in the same direction as the hands of a clock. Therefore, "counterclockwise" means ... ?? Please speak / write in terms of "clock hands" and not in terms of "left"
or "right" in a circle.

Answer 17

in a curve corresponding in direction to the typical forward movement of the hands of a clock.

Answer 18

Good. That's "clockwise." "counterclockwise is in the opposite direction, which just happens to be the direction in which we say our central angle is increasing.

Answer 19

ok...

Answer 20

You are rotating these 3 points counterclockwise about the origin.

Answer 21

right

Answer 22

Again, look at (0,3). Draw a ray from the origin to this point. Then rotate the ray and point counterclockwise about the origin. Where do you end up?

Answer 23

(-3, 0)

Answer 24

In other words, what are the coordinates of your point K' AFTER this rotation" Yes. You now have K'.

Please do the same thing with Point L. draw a ray from the origin to L. Rotate both ray and point counterclockwise 90 degrees. What are the new coordinates of K'?

Answer 25

alright i think i've got it. thanks for your help.

Answer 26

You're welcome, Vera. Good luck!