Posted by **janine** on Monday, July 18, 2011 at 5:17pm.

The image of the point (1, -2) after a rotation of 180° about the origin is

- math -
**Damon**, Monday, July 18, 2011 at 5:35pm
(-1,+2) by inspection

using 90 deg matrix

R90 =

|+0 -1|

|+1 +0|

R180 is R90 * R90

|+0 -1||+0 -1|

|+1 +0||+1 +0|

which is

|-1 +0|

|+0 -1|

- continued -
**Damon**, Monday, July 18, 2011 at 5:36pm
|-1 +0| |+1|

|+0 -1| |-2|

= (-1, +2 )

## Answer This Question

## Related Questions

- geometry - The image of the point (1, -2) after a rotation of 180° about the ...
- geometry - The image of the point (1, -2) after a rotation of 180° about the ...
- geometry - The image of the point (1, -2) after a rotation of 180° about the ...
- math - Point E(0, -2) is a vertex of square DEFG. After a 90* clockwise rotation...
- math, PLEASE HELP! - Point E(0, -2) is a vertex of square DEFG. After a 90* ...
- Math Pre-Algebra HELP - 1. Point E (0,-2) is a vertex of square DEFG. After a 90...
- MATH HELP PLEASE! - Graph these points. Angle DFG has vertices D (–2, 4), F (–3...
- AlgebraB - Help! I have to graph my answer to this problem: ADFG has vertices D...
- algebra - Point D(-3,5) is a vertex of triangle DEF. After rotation of the ...
- geometry - Question 4.4. Which is true about a rotation? (Points : 1) The image ...

More Related Questions