5+4х+3х-х=5+6х
1)при х=25
5+6*25=5+150=155
2)при х=-23
5+6*(-23)=5-138=-133
3)при х=0
5+6*0=5+0=5
431.
а) (5/12 + 3/8) * 12/19
1)5/12 + 3/8 = 10/24 + 9/24 = 19/24
2)19/24 * 12/19 = 1/2
б)6/7(11/18- 5/12)
1)11/18 - 5/12 = 22/36 - 15/36 = 17/36
2)6/7 * 17/36 = 17/42
в) (3 1/14 - 2 5/7)*(7 - 6 3/5) =
1)3 1/14 - 2 5/7 = 1 1/14 - 10/14 = 14/14 + 1 /14 - 10/14= 5/14
2) 7 - 6 3/5 = 6 5/5 -6 3/5 =2/5
Y = 14-7 y=7
k=13-6 y=7
m= 15-8 m=7
13+e=20 e=20-13 e=7
3+a=10 a=10-3 a=7