Answer:
Step-by-step explanation:
When you have an inequality like this, you can treat it like an equation except for one part. If you ever divide or multiply it by a negative number or variable you have to flip the inequality. if it is equal to as well you keep that though. for instance
-5x ≤ 10
x ≥ -2
Anyway, in your case you have two inequalities, so you have to solve both and see what makes both true.
We'll start with 12x - 39 ≤ 9
12x - 39 ≤ 9 First add 39 to both sides
12x ≤ 48 Now divide both sides by 12, positive so no flipping
x ≤ 4
Next is:
-4x + 3 < -6 First subtract 3 from both sides
-4x < -9 Now divide both sides by -4, which means the sign flips
x > 9/4
Now, without even looking at the answers, what number or numbers are less than or equal to 4 and greater than 9/4? Well we pretty much described it there. All numbers starting from, though not including 9/4, which is 2.25, all the way up to, and including 4. B shows exactly that.
