The measure of AB and EF for the similar triangle ABC and DEF are 4 and 12 respectively.
Similar triangles are triangles that have the same shape, but their sizes may vary.
In similar triangles, corresponding sides are always in the same ratio. The angles are congruent.
ΔABC is similar to ΔDEF. Therefore, the sides will form a ratio.
AC / DF = BC / EF = AB/DE
AC = 10
DF = 20
DE = 8
BC = 6
Hence,
10 / 20 = AB / 8
cross multiply
20AB = 80
AB = 80 / 20
AB = 4
Hence,
10 / 20 = 6 / EF
10EF = 120
EF = 120 / 10
EF = 12
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