5х+3х+2=230
5х+3х=230-2
8х=228 |÷8
х=28,5-в теплицах
28,5+2=30,5-в парке
у=4х2-1/2х-1=х2+х/х=х3/х= 3 х/х
1)-3/7x^2-6/7xy-3/7y^2=-3y^2-6xy-3x^2=3y^2+6xy+3x^2=(
![\sqrt{3}](https://tex.z-dn.net/?f=%20%5Csqrt%7B3%7D%20)
y+
![\sqrt{3}](https://tex.z-dn.net/?f=%20%5Csqrt%7B3%7D%20)
x)^2
2)4m(2-n)-6+3n=4m(2-n)-3(2-n)=4m-3
3)x^3-4x^2-x+4=x^3-x-4x^2+4=x(x^2-1)-4(x^2-1)=x-4
4)-1/8a^2+1/4ab-1/8b^2=1/8a^2-1/4ab+1/8b^2=1/4a^2-1/2ab+1/4b^2=(1/2a-1/2b)^2
5)3a(b-4)-2b+8=3a(b-4)-2(b-4)=3a-2
6)x^3+3x^2-x-3=x^3-x+3x^2-3=x(x^2-1)+3(x^2-1)=x+3