35 + 1x = 200 – 140
x = – 140 + 200 – 35
x = 25
490 – 1x = 100 + 210
– x = 210 + 100 – 490
-x = -180
x = 180
200 + 1x = 280 + 600
x = 600 + 280 – 200
x = 680
35 + 1x = 200 – 140
x = – 140 + 200 – 35
x = 25
490 – 1x = 100 + 210
– x = 210 + 100 – 490
-x = -180
x = 180
200 + 1x = 280 + 600
x = 600 + 280 – 200
x = 680