In this lesson, we learn to identify if certain numbers are the solutions to a one-step linear inequality. We plug these numbers one by one and see if the inequality is true. Those numbers for which the one-step inequality is true are identified as solutions to that inequality.
To find solutions to one-step linear inequalities, knowledge of the properties of inequality like the additive and multiplicative property of inequality is necessary.
Identify the correct solution to the following one-step linear inequality
x + 8 > 14
A) 5
B) 6
C) 4
D) 7
Step 1:
x + 8 > 14; x > 14 − 8; x > 6
Plugging in 5, we get 5 > 6; wrong
Plugging in 6, we get 6 > 6; wrong
Plugging in 4, we get 4 > 6; wrong
Plugging in 7, we get 7 > 6; correct
Step 2:
So, the correct solution is 7
Identify the correct solution to the following one-step linear inequality
3x ≤ 12
A) 7
B) 6
C) 5
D) 3
Step 1:
3x ≤ 12
Plugging in 7, we get 3×7 ≤ 12; 21≤12; wrong
Plugging in 6, we get 3×6 ≤ 12; 18≤12; wrong
Plugging in 5, we get 3×5 ≤ 12; 15≤12; wrong
Plugging in 3, we get 3×3 ≤ 12; 9≤12; correct
Step 2:
So, the correct solution is 3