You can put 3 in for x and see which on is true ----------------------------------------------------------------------------------------------------------------- Inequality A
6(3) + 18 < 30
Multiply
18 + 18 < 30
Add
36 < 30
This is not true so this is not the answer ------------------------------------------------------------------------------------------------------ Inequality B
8(3) - 4 < 10
Multiply
24 - 4 < 10
Subtract
20 < 10
This is not true so this is not the answer ------------------------------------------------------------------------------------------------------ Inequality C
10(3) + 10 < 37
Multiply
30 + 10 < 37
Add
40 < 37
This is not true so this is not the answer ------------------------------------------------------------------------------------------------------ Inequality D
15(3) - 10 < 40
Multiply
45 - 10 < 40
Subtract
35 < 40
This is true so this is the answer ------------------------------------------------------------------------------------------------------ The answer is D) 15x - 10 < 40