![24y^3 - 3(8y^2-1)(y+6)](https://tex.z-dn.net/?f=24y%5E3+-+3%288y%5E2-1%29%28y%2B6%29)
при y= -
![\frac{2}{3}](https://tex.z-dn.net/?f=+%5Cfrac%7B2%7D%7B3%7D+)
![24y^3 - 3(8y^2-1)(y+6)](https://tex.z-dn.net/?f=24y%5E3+-+3%288y%5E2-1%29%28y%2B6%29)
=
=
![24y^3 - 3(8y^3 - y + 48 y^{2} - 6 ) =](https://tex.z-dn.net/?f=24y%5E3+-+3%288y%5E3+-+y+%2B+48+y%5E%7B2%7D+-+6+%29+%3D)
=
![24y^3 - 24y^3 + 3y - 144 y^{2} + 18 =](https://tex.z-dn.net/?f=24y%5E3+-+24y%5E3+%2B+3y+-+144+y%5E%7B2%7D+%2B+18+%3D)
=
![- 144 y^{2} + 3y + 18](https://tex.z-dn.net/?f=-+144+y%5E%7B2%7D++%2B+3y+%2B+18)
y= -
![\frac{2}{3}](https://tex.z-dn.net/?f=+%5Cfrac%7B2%7D%7B3%7D+)
![- 144 * (-\frac{2}{3}) ^{2} + 3* (- \frac{2}{3}) + 18 =](https://tex.z-dn.net/?f=-+144+%2A+%28-%5Cfrac%7B2%7D%7B3%7D%29+%5E%7B2%7D+%2B+3%2A+%28-+%5Cfrac%7B2%7D%7B3%7D%29++%2B+18+%3D)
![- 144 * \frac{4}{9} - 2 + 18 = - 64 + 16 = -48](https://tex.z-dn.net/?f=-+144+%2A+%5Cfrac%7B4%7D%7B9%7D+-+2++%2B+18+%3D++-+64+%2B+16+%3D+-48)
![40 m^3 - (5m^2 + m - 2 )(8m + 3)](https://tex.z-dn.net/?f=40+m%5E3+-+%285m%5E2+%2B+m+-+2+%29%288m+%2B+3%29+)
при m=
![\frac{7}{10}](https://tex.z-dn.net/?f=%5Cfrac%7B7%7D%7B10%7D)
![40 m^3 - (5m^2 + m - 2 )(8m + 3) =](https://tex.z-dn.net/?f=40+m%5E3+-+%285m%5E2+%2B+m+-+2+%29%288m+%2B+3%29+%3D)
=
![40 m^3 - (40m^3 + 15 m^{2} + 8m^{2} + 3m - 16m - 6) =](https://tex.z-dn.net/?f=40+m%5E3+-+%2840m%5E3+%2B+15+m%5E%7B2%7D+++%2B+8m%5E%7B2%7D++%2B+3m+-+16m+-+6%29+%3D)
=
![40 m^3 - (40m^3 + 23 m^{2} - 13m - 6) =](https://tex.z-dn.net/?f=40+m%5E3+-+%2840m%5E3+%2B+23+m%5E%7B2%7D+-+13m+-+6%29+%3D)
=
![40 m^3 - 40m^3 - 23 m^{2} + 13m + 6 =](https://tex.z-dn.net/?f=40+m%5E3+-+40m%5E3+-+23+m%5E%7B2%7D+%2B+13m+%2B+6+%3D)
=
![- 23 m^{2} + 13m + 6](https://tex.z-dn.net/?f=+-+23+m%5E%7B2%7D+%2B+13m+%2B+6)
m=
![\frac{7}{10}](https://tex.z-dn.net/?f=%5Cfrac%7B7%7D%7B10%7D)
= 0.7
- 23 m^{2} + 13m + 6 =
=
![- 23* (0.7)^{2} + 13*(0.7) + 6 =](https://tex.z-dn.net/?f=+-+23%2A+%280.7%29%5E%7B2%7D+%2B+13%2A%280.7%29+%2B+6+%3D)
= - 23 * 0.49 + 9.1 + 6 =
= -11.27 + 15.1 = 3.83
8*3х-8*1/8+4х*2+3*2=9х-3
24х-1+8х+6=9х-3
24х+8х-9х=1-6-3
23х= - 8
х= - 8/23
1. 4+3=7 (костюмов сшили в понедельник и вторник)
2. 7+6=13 (костюмов всего нужно было сшить для спектакля)
Ответ: 13 костюмов
Периметр квадрата - 88 см