Question

Find the length of EC.

Answer 1

CD = 28cm
⇒ AB = 28cm
In right ΔABE,

tan30° = `"BE"/"AB"`

⇒ `(1)/sqrt(3) = "BE"/(28)`

⇒ BE = `(28)/sqrt(3)`
In right ΔABC,
tan60° = `"CB"/"AB"`

⇒ `sqrt(3) = "CB"/(28)`
⇒ CB = `28sqrt(3)`
∴ Length of EC
= CB + BE

= `28sqrt(3) + (28)/sqrt(3)`

= `(84 + 28)/sqrt(3)`

= `(112)/sqrt(3)`.