Question

the sum of length,breath,hight of a cuboid is 17cm. length of its diagonal is 13cm find TOTAL SURFACE AREA​

Answer 1

tsa = 2 (lb+bh+hl)

2 (17×17 +17× 17 +17×17)

=1734

Answer 2

From question,

Sum of length, breadth, height= l+b+h= 17cm.

Length of diagonal= 13cm.

Root over( l^2 + b^2 + h^2)= 13cm.

Squaring on both sides,

(l^2+b^2+h^2)=169

We know,

(l+b+h)^2= l^2+b^2+h^2+2(lb+bh+lh)

289= 169+2(lb+bh +lh)

60cm= lb+bh+lh

We know,

TSA= 2(lb+bh+lh)

= 2(60)

= 120 sq.cm.

Hope you have understood.