A triangle has corners at (3, 4 )(3,4), ( 6, 3 )(6,3), and ( 7 , 2 )(7,2). If the triangle is dilated by 5 x5x around (1, 1)(1,1), what will the new coordinates of its corners be?

1 Answer
Jim G.
Nov 25, 2017

(11,16),(26,11)" and "((31,6)(11,16),(26,11) and ((31,6)

Explanation:

"let the points be A, B and C and their images A', B' and C'"let the points be A, B and C and their images A', B' and C'

"let the centre of dilatation be "D(1,1)let the centre of dilatation be D(1,1)

vec(DA')=color(red)(5)vec(DA)=5(ula-uld)

=5[((3),(4))-((1),(1))]=5((2),(3))=((10),(15))

rArrA'=(1+10,1+15)=(11,16)

vec(DB')=color(red)(5)vec(DB)=5(ulb-uld)

=5[((6),(3))-((1),(1))]=5((5),(2))=((25),(10))

rArrB'=(1+25,1+10)=(26,11)

vec(DC')=color(red)(5)vec(DC)=5(ulc-uld)

=5[((7),(2))-((1),(1))]=5((6),(1))=((30),(5))

rArrC'=(30+1,5+1)=(31,6)

Related questions
See all questions in Dilations or Scaling around a Point
Impact of this question
1930 views around the world
You can reuse this answer
Creative Commons License