| 2x + 1 | >= 10
Two cases to consider, the first is 2x + 1 <= -10
2x + 1 <= -10
2x <= -11
x <= -11/2
—
2nd case: 2x + 1 >= 10
2x + 1 >= 10
2x >= 9
x >= 9/2
—
The solution regions are and
For me, it is a MYSTERY what this post/this condition means . . .
And the best service from my side to the author of this post is to say that this formulation is mathematically incorrect . . .
In my view, not only it is mathematically incorrect formulation.
It is incorrect from the English grammar, word usage and the sentence construction point of view, too . . .
But if you change it in this way
Twice a number is no less than 10 units from -1
or even better
Twice a number is / no closer than 10 units from -1