Question

Find the missing length indicated.

Answer 1

? = 28

Explanation:

A line parallel to a side of a triangle and intersecting the other two sides, divides those sides proportionally , that is

`(?)/(35-?)` =
`(15-3)/(3)` =
`(12)/(3)` = 4 ( multiply both sides by 35 - ? )

? = 4(35 - ? ) ← distribute parenthesis

? = 140 - 4? ( add 4? to both sides )

5? = 140 ( divide both sides by 5 )

? = 28