Question

HELP PLEASE!! ASAP
If triangles ABC and DEF are similar, what is y? Show your work.

Answer 1

If both triangles are similar then ratio of sides will be same.

`\\ \sf\longmapsto (12)/(14)=(y)/(21)`

`\\ \sf\longmapsto 12(21)=14y`

`\\ \sf\longmapsto 14y=252`

`\\ \sf\longmapsto y=(252)/(14)`

`\\ \sf\longmapsto y=18`

Answer 2

y = 18

Explanation:

Since the triangles are similar, the corresponding sides are in proportion, that is

`(BC)/(EF)` =
`(AC)/(DF)` , substitute values

`(y)/(12)` =
`(21)/(14)` ( cross- multiply )

14y = 252 ( divide both sides by 14 )

y = 18