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.

Question

asked Jan 23, 2019 202k views

1 Answer

Tushar H · Answer 1 · 2019-01-29T04:07:57+0000

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.