8^7 + 4^11 = (2^3)^7 + (2^2)^11 = 2^21 + 2^22 = 2^21 + 2*2^21 = (2 + 4)^21 = 6<span>^21; 6/3
</span>5^7 + (5^2)^3 = 5^7 + 5^6 = (25 + 5)^6 = 30<span>^6; 30/30
</span>
1. a11=a1+10d.
a11=-3+7=4.
2. a20=a1+19d.
a20=18-19•0.5=8.5
3. a5=a1+4d.
a5=20+4•3=32.
4. a21=a1+20d.
a21=5.8-20•1.5=-25.8
7-12x+4=5-10x
-10x+12x=7+4-5
2x=6
x=6/2
x=3
X-y=2
2x-2y=2a
x=2+y
2(2+y)-2y=2(2+y)
x=2+y
4+2y-2y=4+2y
x=2+y
-2y=0
Дальше сам
№1 а) -7аb
б) 16х-24
в) -12+3х
№2 а) х+5+4х-6=5х-1
б) 3х-2-5х+8=-2х+6
в)20+y-20=y
№3 2a-8-1+2a=4a-9= 4*(-1,5)-9=-15
№4 16y-40-12y+40-4y
16y-12y-4y=-40+40
0=0
№5 z-(y+z-t)=z-y-z+t=-y+t