Use a rotation matrix to rotate figure DEFGH clockwise 90º. If the figure has coordinates D (1, 3), E (3, 2), F (1, -1), G (-3, -2), and H (-2, 2), which

D (1, 3), E (3, 2), F (1, -1), G (-3, -2), and H (-2, 2), which statement is true about figure D'E'F'G'H'? 

D (1, 3),  1st quad goes to 4th quad D'(3,-1)      swap numbers, x is pos and y is neg

E (3, 2),      As above  E'(2-3)

F (1, -1),    the quad goes to 3rd quad   swap the abs numbers, x is neg y is neg    F'(-1,-1)

G (-3, -2)    third quad goes to 2nd quad  swap the numbers , x is neg y is pos  G'(-2,3)

H (-2, 2), second quad goes to 1st quad,  swap the numbers,  x is pos and y is pos    H'(2,2)

Why don't you join up properly - there are lots of benefits and no disadvanges - it is really easy.  :)

If you used the clockwise matrix times the matrix of points, the matrix solution would give you the new points:

|   cos90    sin90  |    X    |  1  3  1  -3  -2  |       =  |                             |                         

| -sin90    cos 90  |          |  3  2  -1  -2  2  |            |                            |

Where the first column in your answer matrix represents D', the second column represents E', etc.

Let me add something, Tori ....rotating a point  in a quadrant either 90 degrees clockwise or counter-clockwise simply puts the point in the next quadrant (for 90 degrees clockwise) or the prior quadrant (for 90 degrees counter-clockwise). As long as you remember the signs on x and y in each quadrant, you might not even have to do much "math' in these kinds of problems. For instance, "A" is the correct choice here, because it's the only one that makes logical sense.  "E" is a first-quadrant point whose signs are both positive. And when we rotate it 90 degrees clockwise, it ends up in the 4th quadrant where x is positive and y is negative. Look at the rest of the answers......the signs are incorrect for each point......we don't even have to look at the values in this case !!!!