A triangle has corners at (4, 5 )(4,5), ( 4, 3 )(4,3), and ( 4 , 2 )(4,2). If the triangle is dilated by 2 x2x around (1, 0)(1,0), what will the new coordinates of its corners be?

1 Answer
Feb 12, 2018

New coordinates of the corners are color(blue)(A' (7,10), color(blue)(B' (7,6),color(blue)(C' (7,4)

Explanation:

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Given : A (4,5), B (4,3), C(4,2)

Dilated about D(1,0) and dilation factor 2

To find the new coordinates of the corners

vec(A'D) = 2 * vec(AD)

a' - d = 2(a - d) or a' = 2a - d

=> 2((4),(5)) - ((1),(0)) = ((7),(10))

color(blue)(A' (7,10)

vec(B'D) = 2 * vec(BD)

b' - d = 2(b - d) or b' = 2b - d

=> 2((4),(3)) - ((1),(0)) = ((7),(6))

color(blue)(B' (7,6)

vec(C'D) = 2 * vec(CD)

c' - d = 2(c - d) or c' =2c - d

=> 2((4),(2)) - ((1),(0)) = ((7),(4))

color(blue)(C' (7,4)