1) 3(a-b) - 2(a+b) = 3a-3b-2a-2b= a-b
2) 4(x+y) + 5(2x-y) = 4x+4y+10x-5y = 14x-y
3) 2.4(c-3b)-1.3(2c-d) = 2.4c-7.2b-2.6c-1.3d = -0.2c -7.2b-1.3d
4) -
![\frac{3}{4}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B4%7D+)
(
![\frac{1}{3}](https://tex.z-dn.net/?f=+%5Cfrac%7B1%7D%7B3%7D+)
m+n) -
![\frac{1}{4}](https://tex.z-dn.net/?f=+%5Cfrac%7B1%7D%7B4%7D+)
(3m+n) = -
![\frac{1}{4}](https://tex.z-dn.net/?f=+%5Cfrac%7B1%7D%7B4%7D+)
m -
![\frac{3}{4}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B4%7D+)
n -
![\frac{3}{4}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B4%7D+)
m+n =
![\frac{3}{16}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B16%7D+)
m -
![\frac{4}{5}](https://tex.z-dn.net/?f=+%5Cfrac%7B4%7D%7B5%7D+)
n
Сперва находишь l - образующую конуса.
По теореме Пифагора
l=√h2+r2=√144+25=√169=18
h - высота, r - радиус.
S(конуса)= Πr(r+l)=5Π×(5+13)=5Π×18=90Π
Ответ:90Π
<em><u>(1-2+3)*4*5=40</u></em> <em><u> </u></em><span><em><u>(-1+2+3)*4*5=80</u></em>
</span>2*4*5=8*5=40 4*4*5=16*5=80
Эм...пирамида
вроде так,
да,так
1,5 га=15000 м2
1,5 а=150 м2...................................