Răspuns :
a + b = 500
a + 100 = b
a + a + 100 = 500
2a = 500-100
2a = 400
a = 400 : 2 = 200
b = a + 100 = 200 + 100 = 300
a + 100 = b
a + a + 100 = 500
2a = 500-100
2a = 400
a = 400 : 2 = 200
b = a + 100 = 200 + 100 = 300