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Question
A triangle ABC is enlarged, about the point O as centre of enlargement, and the scale factor is 3. Find : OC', if OC = 21 cm.
Also, state the value of :
- `(OB^')/(OB)`
- `(C^'A^')/(CA)`
Solution
Given that triangle ABC is enlarged and the scale factor is m = 3 to the triangle A'B'C'.
OC = 21 cm
So, (OC)3 = OC'
i.e. 21 × 3 = OC'
i.e. OC' = 63 cm
The ratio of the lengths of two corresponding sides of two similar triangles
a. Given that ABC is enlarged and the scale factor m = 3 to the triangle A'B'C'.
`=> (OB^')/(OB) = 3`
b. Given that ABC is enlarged and the scale factor m = 3 to the triangle A'B'C'
`=> (C^'A^')/(CA) = 3`
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