Question

A cuboid is twice as long as its breath and its is 6cm high.if its total surface is 544cm
,then find the length and breath ​

Answer 1

Answer:

let the breadth of cuboid be x

then the length of cuboid =2x

height of the cuboid =6cm

total surface of cuboid=2lb+2lh+2bh

544 = 2×2x×x +2×2x×6+2×x×6

544 = 4x*2+24x+12x

544 = 4x*2+36x

544 = 4x(x+9)

544/4 = x*2+9x

136 = x*2+9x

x*2+9x - 136 = 0

x*2+17x-8x-136 = 0

x(x+17)-8(x+17) = 0

( x+17) (x-8) = 0

x+17 = 0

x= -17 (does not exist)

x-8 = 0

x=8

the breadth of cuboid = x = 8cm

the length of cuboid = 2x = 8×2 = 16cm