Answer: a ≤ 4 or (-∞, 4]
Explanation:
Here we have the inequality:
4a ≤ 16
this means that the left sides is less or equal than the right side.
First, find the equal part:
4*a = 16
a = 16/4 = 4
So the maximum possible value of a is 4.
Now, all the values of a smaller than 4 also make the inequality true (even the negative values) so the possible values of a are:
a ≤ 4 or (-∞, 4]