Question

Let triangle ABC is congruent to triangle DEF.if area of triangle abc is 100 cmsq
An area of triangle def is 196cmsq and de is 7cm .find ab

Answer 1

∴

ar(△DEF)

ar(△ABC)

=

(DE)

2

(AB)

2

⟹

ar(△DEF)

56

=

(DE)

2

(2DE)

2

[given]

⟹

ar(△DEF)

56

=

(DE)

2

4(DE)

2

⟹ar(△DEF