1. The sum of twice a number and 5 is at most 15. What are the possible values for the number?

x > 5

Step-by-step explanation:

Let's call our mysterious number as x.

2x + 5 > 15

The trick here is to solve it like a normal equation.

Subtract 5 from both sides

2x > 10

divide both sides by 2

x > 5

The values are everything above 5.

Note*: The only thing you need to know in the way I did this is to switch the sign if you're dividing by a negative.

Answer: 0 (if 0 is counted), 1, 2, 3, 4, 5

Step-by-step explanation: These (not including 0) are positive values. The number of negative integers is infinite.