# Math

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If ∆ ABC ~ ∆ DEF, BC = 12 cm, EF = 10 cm, and AC = 18 cm, find DF.

• Math -

The triangles are similar (but not congruent).

That means that corresponding sides are all in the same ratio.
BC/EF = 12/10 = AC/DF = 18/DF

DF = 18*(5/6) = 15

• Math -

by ratios

DF/10 = 18/12

solve for DF

• Math -

Please do not repost the same question without checking if your last post has been answered.
It causes unnecessary work by the tutors

http://www.jiskha.com/display.cgi?id=1294796964

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