1.
1 3/32 * (-1 19/45)+1 17/63 * 3 9/25=2 32/45
1) 1 3/32 * (-1 19/45)= - 35/32 * 64/45= - 14/9= - 1 5/9
2) 1 17/63 * 3 9/25=80/63 * 84/25=64/15=4 4/15
3) - 1 5/9+4 4/15= - 1 25/45+4 12/45=2 32/45
2.
(3с+а)/4с - (а-7с)/4с=(3с+а-а+7с)/4с=10с/4с=2 1/2=2,5
4/(х+4) - х/(х-4)=(4(х-4)-х(х+4)) / ((х+4)(х-4))=(4х-16-х² -4х)/(х²-16)=(-16-х²)/(х²-16)
3.
(2ab+4b)/3a * 6a²/(a²b -4b)=(2b(a+2)*2a) / (b(a-2)(a+2))=4a/b
4.
(3x² y^-3)/z : ((3x)³z^-2)/y^5=3x²/zy³ * y^5z²/9x³=y²z/3x
5.
25x- x^-1 =0
25x - 1/x=0
25x²-1=0
(5x-1)(5x+1)=0
5x-1=0
5x=1
x1=0.2
5x+1=0
5x= -1
x= -0.2
x= +-0.2