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If d 3/4 (PQR)=(P’Q’R), what are the coordinates of r?

A. (4/3,-4)
B. (3/4,-9/4)
C. (3,4)
D. (-9/4,0)
Please help! I just don’t understand how to do this.

If d 3/4 (PQR)=(P’Q’R), what are the coordinates of r? A. (4/3,-4) B. (3/4,-9/4) C-example-1
User Peter Lang
by
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1 Answer

3 votes

Answer: The correct option is B.

Step-by-step explanation:

From the figure it is noticed that the coordinates of option point R is (1,-3).

The statement,


d_{(3)/(4)(PQR)=P'Q'R'

Means dilation of triangle PQR with scale factor
(3)/(4) and center at origin, then the image is P'Q'R'.

If the dilation with factor k and center at origin, then


(x,y)\rightarrow(kx,ky)

Since the coordinates of R is (1,-3) and the scale factor is
(3)/(4).


R(x,y)\rightarrow R'((3)/(4)x,(3)/(4)y )


R(1,-3)\rightarrow R'((3)/(4)*1, (3)/(4)*(-3))


R(1,-3)\rightarrow R'((3)/(4), (-9)/(4))

Therefore the correct option is B.

User Tushar H
by
6.5k points