<span>Найдём значение выражения:
- (</span><span>
- </span><span>
)=0,21) </span><span>
![\frac{9}{35}](https://tex.z-dn.net/?f=+%5Cfrac%7B9%7D%7B35%7D+)
-
![\frac{3}{28}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B28%7D+)
= </span>
![\frac{4*9}{4*35}](https://tex.z-dn.net/?f=+%5Cfrac%7B4%2A9%7D%7B4%2A35%7D+)
-
![\frac{5*3}{5*28}](https://tex.z-dn.net/?f=+%5Cfrac%7B5%2A3%7D%7B5%2A28%7D+)
=
![\frac{36}{140}](https://tex.z-dn.net/?f=+%5Cfrac%7B36%7D%7B140%7D+)
-
![\frac{15}{140}](https://tex.z-dn.net/?f=+%5Cfrac%7B15%7D%7B140%7D+)
=
![\frac{36-15}{140}](https://tex.z-dn.net/?f=+%5Cfrac%7B36-15%7D%7B140%7D+)
=
![\frac{36-15}{140}](https://tex.z-dn.net/?f=+%5Cfrac%7B36-15%7D%7B140%7D+)
=
![\frac{21}{140}](https://tex.z-dn.net/?f=+%5Cfrac%7B21%7D%7B140%7D+)
=
![\frac{7*3}{7*20}](https://tex.z-dn.net/?f=+%5Cfrac%7B7%2A3%7D%7B7%2A20%7D+)
=
![\frac{3}{20}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B20%7D+)
2)
![\frac{7}{20}](https://tex.z-dn.net/?f=+%5Cfrac%7B7%7D%7B20%7D+)
-
![\frac{3}{20}](https://tex.z-dn.net/?f=+%5Cfrac%7B3%7D%7B20%7D+)
=
![\frac{7-3}{20}](https://tex.z-dn.net/?f=+%5Cfrac%7B7-3%7D%7B20%7D+)
=
![\frac{4}{20}](https://tex.z-dn.net/?f=+%5Cfrac%7B4%7D%7B20%7D+)
=
![\frac{4}{4*5}](https://tex.z-dn.net/?f=+%5Cfrac%7B4%7D%7B4%2A5%7D+)
= <span>
![\frac{1}{5}](https://tex.z-dn.net/?f=+%5Cfrac%7B1%7D%7B5%7D+)
= 0,2</span>
Допустим одно число х, тогда второе y. Получается
х+y=45.7
x=1.5y
1.5y+y=45.7
2.5y=45.7
y=18.28
x=18.28*1.5=27.42
..............................
Нарисуй квадрат по 5см стороны
45*(2/5) + 30*(2/5) =18 +12 =30