4-2(X-5)≤4X-1

-2x+10≤4x-1
+2x +2x

4+10≤6x-1
+1 +1

4+11≤6x

answer is 15 ≤6x

watch the order of operation ...

4-2(X-5)≤4X-1
4 - 2x + 10 ≤ 4x - 1
-2x - 4x≤ -1 - 4 - 10
-6x ≤ -15
6x ≥ 15
x ≥ 15/6
x ≥ 5/2