105 - x + 1 = 99
105 - x = 99 - 1
105 - x = 98
x = 105 - 98
x = 7
150 - x + 1 = 99
150 - x = 99 - 1
150 - x = 98
x = 150 -98
x = 52
105 - x +1 = 99
x +1 = 105 - 99
x + 1 = 6
x =6 -1
x =5
150 - x + 1 = 99
=> 150 - x = 99 - 1
=> 150 - x = 98
=> -x = 98 + 150
=> -x = 248
=> x = -248