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 :

1. `(OB^')/(OB)`
2. `(C^'A^')/(CA)`

Answer 1

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`