Question

I need help with this question about similar triangles

Answer 1

ST = 12 units

Explanation:

Δ RAS and Δ TES are similar triangles, thus the ratios of corresponding sides are equal, that is, noting that SR = 21 - ST, thus

`(ST)/(SR)` =
`(TE)/(AR)` substitute values

`(ST)/(21-ST)` =
`(8)/(6)` ( cross- multiply )

6ST = 8(21 - ST)

6ST = 168 - 8ST ( add 8ST to both sides )

14ST = 168 ( divide both sides by 14 )

ST = 12