1) <span>4x+7= -28 - x
4х+х=-28-7
5х=-35
х=-35:5
х=-7
2)</span><span>2(3 - 4x) - 5= 6 - 7(x+8)
6-8х-5=6-7х-56
-8х+7х=6-56-6+5
-х=-51
х=51</span>
1)133,
2)156,
3)420,
4)420.
(40^50)*(50^40)
(2^50)*(2^50)*(10^50)*(5^40)*(10^40)
(2^40)*(5^40)*(10^90)*(2^60)
(10^40)*(10^90)*(2^60)
(2^60)*(10^130)
Ответ: 130.