Answer:
A. [tex]7x+39 \geq 53[/tex]
=> [tex]7x \geq 53-39[/tex]
=> [tex]7x \geq 14[/tex]
=> [tex]x\geq 2[/tex]
The solution is the interval is [2,∞)
B. [tex]16x+15>31[/tex]
=> [tex]16x>31-15[/tex]
=> [tex]16x>16[/tex]
=> x >1
The solution is (1,∞)
Now, the solution of the inequality A AND B is equal to
[2,∞) ∩ (1,∞)=[2,∞)
