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Question
ΔXYZ is enlarged to ΔX'Y'Z'. If XY = 12cm, YZ = 8cm and XZ = 14cm and the smallest side of ΔX'Y'Z' is 12cm, find the scale factor and use it to find the length of the other sides of the image ΔX'Y'Z'.
Solution
Scale factor =`"Image length"/"Actual length"`
Scale factor = `(12)/(8)` = 1.5
`"X'Y'"/"XY"` = 1.5
⇒ X'Y' = 1.5 x 12
⇒ X'Y' = 18cm
`"X'Z'"/"XZ"` = 1.5
⇒ X'Z' = 1.5 x 14
⇒ X'Z' = 21cm.
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