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Triangle PQR has vertices P(−3,4), Q(−8,3), and R(−1,−6). Triangle PQR is dilated by a scale factor of 8 centered at the origin to get triangle P′Q′R′.

What are the coordinates of points P′, Q′, and R′ of the image?

P′(−38,−12), Q′(−1,38), R′(−18,−34)
P′(−3,32), Q′(−8,24), R′(−1,−48)
P′(−24,4), Q′(−64,3), R′(−8,−6)
P′(−24,32), Q′(−64,24), R′(−8,−48)

2 Answers

1 vote

Answer:

(-24, 32), (-64, 24) and (-8,-48)

Explanation:

User QRohlf
by
6.5k points
6 votes

Answer:

The coordinates of points P', Q' and R' are (-24, 32), (-64, 24) and (-8,-48), respectively.

Explanation:

Vectorially speaking, the dilation of a vector with respect to a given point is defined by the following formula:


P'(x,y) = O(x,y) + r\cdot [P(x,y)-O(x,y)],
r > 1 (1)

Where:


O(x,y) - Point of reference.


P(x,y) - Original point.


P'(x,y) - Dilated point.


r - Scale factor.

If we know that
O(x,y) = (0,0),
P(x,y) = (-3, 4),
Q(x,y) = (-8,3),
R(x,y) = (-1,-6) and
r = 8, then the new coordinates of the triangle are, respectively:


P'(x,y) = (0,0) + 8\cdot [(-3,4)-(0,0)]


P'(x,y) = (-24, 32)


Q'(x,y) = (0,0) + 8\cdot [(-8,3)-(0,0)]


Q'(x,y) = (-64, 24)


R'(x,y) = (0,0) + 8\cdot [(-1,-6)-(0,0)]


R'(x,y) = (-8,-48)

The coordinates of points P', Q' and R' are (-24, 32), (-64, 24) and (-8,-48), respectively.

User Excel Hero
by
5.6k points