I think those are coordinates of points, (-5,8) and (-2,8)
so you just need to use distance formula ((8-8)^2+(-2+5)^2)=0+9=9
square root 9=3
I would suggest factoring using the grouping method. The answer I got was (2n-1)(n+2)
-3(5 + 8x) - 20 ≤ -11 |use distributive property: a(b + c) = ab + ac
-15 - 24x - 20 ≤ -11
-35 - 24x ≤ -11 |add 35 to both sides
-24x ≤ 24 |change signs
24x ≥ -24 |divide both sides by 24
x ≥ -1