Держи...........................................
<span>х:12×5=40
х:12=40:5
х:12=8
х=8*12
х=96
</span><span>Х×5=12×40
х*5=480
х=480:5
х=96
</span><span>Х+40=12×5
х+40=60
х=60-40
х=20</span>
S=2ab+2bc+2ac ,a=2 дм, b=3 дм, с=11 дм
S=2×2×3+2×3×11+2×2×11=12+66+44=122 см²