Use deductive reasoning to prove that [tex]$x = -3$[/tex] is not in the solution set of the inequality [tex]-4x \ \textless \ 8[/tex]. Be sure to justify each step in your proof.



Answer :

Sure, let's go through the steps to prove whether [tex]\( x = -3 \)[/tex] satisfies the inequality [tex]\( -4x < 8 \)[/tex].

### Step-by-Step Solution:

1. Substitute [tex]\( x = -3 \)[/tex] into the inequality:
- The given inequality is [tex]\( -4x < 8 \)[/tex].
- Substitute [tex]\( x = -3 \)[/tex] into the left-hand side of the inequality:
[tex]\[ -4(-3) \][/tex]

2. Simplify the left-hand side:
- When we multiply [tex]\(-4\)[/tex] by [tex]\(-3\)[/tex], we get:
[tex]\[ -4 \times (-3) = 12 \][/tex]

3. Evaluate the inequality:
- Substitute [tex]\( 12 \)[/tex] back in for the left-hand side:
[tex]\[ 12 < 8 \][/tex]
- Now, let's evaluate whether this statement is true or false.

4. Check the truth of the statement:
- Clearly, [tex]\( 12 \)[/tex] is not less than [tex]\( 8 \)[/tex].
[tex]\[ 12 \geq 8 \][/tex]
- Therefore, [tex]\( 12 < 8 \)[/tex] is a false statement.

### Conclusion:
Since the statement [tex]\( 12 < 8 \)[/tex] is false, it means that substituting [tex]\( x = -3 \)[/tex] into the inequality [tex]\( -4x < 8 \)[/tex] does not satisfy the inequality. Thus, [tex]\( x = -3 \)[/tex] is not in the solution set of the inequality [tex]\( -4x < 8 \)[/tex].