2-x
3x-20=x+10
3x-x=10+20
2x=30:2
x=15(т)-2 сарай
15*3=45(т)
4x-3/3-2x - 4+5x/3+2x + 3+x-10x^2/9-4x^2 =
=((4x-3)(3+2x)-(4+5x)(3-2x)+3+x-10x^2)/ 9-4x^2 =
=(8x^2 +6x-9+10x^2-12-7x+3+x-10x^2)/ 9-4x^2 =
=(8x^2 -18)/ 9-4x^2= 2(4x^2 -9)/ 9-4x^2 = -2
4х⁴ - 2*(х⁴+1)²=4х⁴ - 2*(х^8+2x^4+1)=4x^4-2x^8-4x^4-2=-2x^8-2=-2(x^8+1)