Question

The number 5 is one of the solutions for the inequality 3x < 21.
True
False

Answer 1

To find the answer, plug in 5 into the inequality. 
3(5)<21
15<21 
Since 15 is less than 21, we know that 5 is a solution. 

Answer 2

lets see...

3(5) < 21
15 < 21...so is 15 less then 21...yes...so 5 is a solution