Решите уравнения.

(490-х) - 250=70

5*а+500=4500:5

а+156=17*20

(1604-у) - 108=800

140 - (а+25) = 40

340 + (190-х) = 400

100 - (х+25) = 52

(11676+34567) - х=11245

(490-x) - 250=70

490-x = 70+250

-x = 320-490

-x = - 170

x = 170

5a+500 = 4500:5

5a = 900-500

5a = 400

a = 80

a+156 = 17*20

a = 340-156

a = 184

(1604-y) - 108 = 800

1604-y = 800+108

-y = 908-1604

-y = - 696

y = 696

140 - (a+25) = 40

a+25 = 140-40

a = 100-25

a = 75

340 + (190-x) = 400

190-x = 400-340

-x = 60-190

-x = - 130

x = 130

100 - (x+25) = 52

x+25 = 100-52

x = 48-25

x = 23

(11676+34567) - x = 11245

-x = 11245-46243

-x = - 34998

x = 34998