Question

ABC is a right angled triangle, where angle B=90° and AB=7cm. the triangle is rotated about AB. the volume of the right cone so formed is found to be 4224 cm^3 . find the other sides of the triangle.
​

Answer 1

Answer:

AB=AC [Given ]

∠A=90

o

∴ ∠C=∠B [ Angles opposite to equal sides are equal ] ---- ( 1 )

In △ABC,

∠A+∠B+∠C=180

o

[ Angles sum property of triangles ]

⇒ 90

o

+∠B+∠C=180

o

⇒ 90

o

+∠B+∠B=180

o

[ From ( 1 ) ]

⇒ 2∠B=90

o

⇒ ∠B=45

o

∴ ∠B=∠C=45

o