Question

Define a variable, write an inequality, and solve each problem. Check your solution.

1. Half of a number is at least 14
2. The opposite of 1/3 a number is greater than 9
3. 1/5 of a number is at most 30

Answer 1

A variable= an unknown number

1. (1/2)x ≥ 14
x ≥ 28
Check:
1/2(28) ≥ 14
14 ≥ 14

2. -(1/3)x > 9
x < -27
Check:
-(1/3)(-30) > 9
10 > 9

3. (1/5)x ≤ 30
x ≤ 150
Check:
(1/5)(140) ≤ 30
28 ≤ 30