Question

Given that two figures are similar, use a scale factor to find the missing length

Answer 1

The missing length x is 99 m.

Solution:

Given polygons are similar.

If two triangles are similar, then the corresponding sides are in proportion.

$\Rightarrow\frac{81}{18}=\frac{x}{22}$

Multiply by 22 on both sides, we get

$\Rightarrow\frac{81}{18}\times 22=\frac{x}{22}\times 22$

$\Rightarrow\frac{9}{2}\times 22=x$

⇒ 9 × 11 = x

⇒ 99 = x

Switch the sides.

⇒ x = 99

The missing length x is 99 m.