Ответ:
(а-3) (а+3) - а (а-4)=a²-9-a²+4a=4a-9
1) <u> 2 </u> + <u> 1 </u>= <u> 2 </u> + <u> 1 </u> = <u>2(3+y)+3-y </u>=
9-6y+y² 9-y² (3-y)² (3-y)(3+y) (3-y)²(3+y)
= <u>6 +2y+3-y </u>= <u> 9+y </u>
(3-y)²(3+y) (3-y)²(3+y)
2) (y-3)² * <u> 9+y </u> = <u>(-1(3-y))² * (9+y) </u> = <u>(-1)² (3-y)² (9+y)</u> =
(3-y)²(3+y) (3-y)²(3+y) (3-y)²(3+y)
= <u>9+y</u>
3+y
3)<u> 2y </u>+ <u> 9+y </u>= <u>2y+9+y </u>=<u> 9+3y </u>= <u>3(3+y) </u>= 3
y+3 3+y y+3 y+3 y+3
Ответ:
-2y+x
Объяснение: -4x+y+5x-3y=x(-4+5)+y(1-3)= x(1)+y(-2)=x+(-2y)=x-2y