Question

the sum of length,breadth and height of a cuboid is 19 cm and it's diagonal is 5root under 5cm. find it's TSA

Answer 1

Let the length ,breadth ,height be l, b, h respectively.

Now, l + b + h = 19 CM.

Given it's diagonal = 5√5 cm.

Diagonal = √ l² + b² + h² = 5√5


125 = l² + b² + h²

Also, T. S. A = 2(lb+bh+hl)

Now, Take l + b + h = 19

Squaring on both sides

(l + b + h) ² = 19²

l² + b ² + h² + 2 ( lb+ bh+hl) = 361

125 + TSA = 361

TSA = 236 cm²

Therefore, T. S. A = 236 cm²

Answer 2

Answer:

Step-by-step explanation:

Let the length ,breadth ,height be l, b, h respectively.

Now, l + b + h = 19 CM.

Given it's diagonal = 5√5 cm.

Diagonal = √ l² + b² + h² = 5√5

125 = l² + b² + h²

Also, T. S. A = 2(lb+bh+hl)

Now, Take l + b + h = 19

Squaring on both sides

(l + b + h) ² = 19²

l² + b ² + h² + 2 ( lb+ bh+hl) = 361

125 + TSA = 361

TSA = 236 cm²

Therefore, T. S. A = 236 cm²