Question

Setelah dicerminkan terhadap titik asal,ΔXYZ memiliki bayangan di memiliki bayangan di X'(1,4), Y'(2,2), dan Z'(-2,-3). Tentukan bayangan segitiga XYZ jika direfleksikan terhadap garis x = -1

Answer 1

Dicerminkan ke titik asal :

x' = -x
y' = -y

1 = -x
4 = -y

x = -1
y = -4

X(-1,-4)

2 = -x
2 = -y

x = -2
y = -2

Y(-2,-2)

-2 = -x
-3 = -y

x = 2
y = 3

Z(2,3)

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jika direfleksikan terhadap x = -1

x' = 2a - x
y' = y

x' = 2(-1) - (-1)
y' = -4

x' = -2 + 1
y' = 4

x' = -1
y' = 4

X'(-1,4)

x' = 2(-1) - (-2)
y' = -2

x' = -2 + 2
y' = -2

x' = 0
y' = -2

Y'(0,-2)

x' = 2(-1) - 2
y' = 3

x' = -2 - 2
y' = 3

x' = -4
y' = 3

Z'(-4,3)

X'(-1,4), Y'(0,-2) dan Z'(-4,3)