1
(x+1,75)*(1/45+2/9)=16,5*7/30
(x+1,75)*(1/45+10/45)=33/2*7/30
(x+1,75)*11/45=77/20
x+1,75=77/20:11/45
x+1,75=77/20*45/11
x+1,75=63/4
x=63/4-7/4
x=56/4
x=14
2
(x²+2x+1)-(y²+4y+4)=(x+1)²-(y+2)²=(x+1-y-2)(x+1+y+2)=(x-y-1)(x+y+3)
3
9x²-24x+16+9x²+24x+16-18x²+8+10=(9x²+9x²-18x²)+(-24x+24x)++(16+16+18)=50