The pair is any numbers, 1 positive and one negative, that add up to -3.
Here is a sample;
(-5, 2)
B is less than or equal to -11
You answer is the third option
If each week the tank decreased by 3 inches, in 2 weeks it would be 6 in, 3 weeks is 9 in, 4 weeks would be 12 in, and 5 weeks would be 15 in.
10= -4 + x x=14 because you do the opposite of the sign you see in this case its a plus sign so you subtract -4 from ten and since the 4 is a negative and your subtracting you would add 4 I know this probably didn't help it sounds really confusing but I have hope that it did :)