Question

ABC is an isosceles right angled at A. If AB=4 cm, then its area is ______.(With full explanation)​

Answer 1

Answer:

$given$

1. ABC is a right angle triangle

ABC is a right angle triangle2. it's also an isosceles triangle

ABC is a right angle triangle2. it's also an isosceles triangle3. Ab = 4cm

ABC is a right angle triangle2. it's also an isosceles triangle3. Ab = 4cm4. A is 90°

$to \: find$

area of triangle Abc

procedure

as it's and isosceles triangle, it's two sides are equal,

so ab = 4cm and ac = 4cm

now, to find 3rd side cb,

by Pythagoras theorem,

(Hypotenuse)² = (Base)² + (Perpendicular)²

(cb)² = (4)² + (4)²

(cb)² = 16 + 16

(cb)² = 32

cb × cb = 5.6 × 5.6 (approx)

so cb = 5.6

now area of triangle = 1/2 × base × height

= 1/2 × 4 × 4 cm

= 8 cm²

hope will help you.....