In $\mathrm{△}ABC,D\backslash triangle\; ABC,\; D$ is the mid point of BC. Then $A{B}^2+A{C}^2=AB^2\; +AC^2\; =$

In $\mathrm{△}ABC\backslash triangle\; ABC$, if ∠B = 90°, BD $\perp \backslash perp$ AC, then

Two ……………. are always similar

Two ……………. are always similar

The perimeters of two similar triangles are 30 cm and 20 cm respectively. If one side of the first triangle is 12 cm, then the corresponding side of the second triangle is …………….. cm

In a $\mathrm{△}ABC,\backslash triangle\; ABC,$ the bisector of $\mathrm{\angle }A\backslash angle\; A$ intersects BC at D. If BD: DC = 4 : 7 and AC = 3.5 then AB =

AD is the angular bisector of ‘A’. If AB = 6 cm, BD = 8 cm and DC = 6 cm, then AC = …………. cm.

ΔABC is similar to ΔDEF is denoted as

$\mathrm{△}ABC\backslash triangle\; ABC$ is congruent to $\mathrm{△}DEF\backslash triangle\; DEF$ is denoted as

Observe the given figures and name the criterion of similarity.