If △ABC ∼ △DEF such that area of △ ABC is 9 cm2 and the area of △DEF is 25cm2 and BC=2.1cm. Find the length of EF.
3.0cm
2.8cm
3.5cm
3.6cm
We haveArea of(△ABC)Area(△DEF)=BC2EF2925=(2.1)2EF235=2.1EF⇒EF=(5×2.1)3cm=3.5 cm
If ΔABC∼ΔDEF such that area of ΔABC is 9 cm2 and the area of ΔDEF is 16 cm2 and BC = 2.1 cm, then the length of EF is