.94sqm=9400sqcm.a cuboid has six faces  let y= height 2x50x70+2x70y+2x50y=9400  ------ 7000+140y+100y= 9400 240y=2400  y=10  the cuboid is 70x50x10

X+5y=15  x=15-5y  3x-y=-3        3(15-5y) -y=-3      45-15y-y+3=0  48 -16y=0 48=16y    y=48    y=3                   16

3x+3=2x+6 subtract2x from both sides we get x+3=6  x=6-3=  3

Because metal conducts the heat away from your hand far quicker than the wood does