Solve the compound inequality 6b < 24 or 4b + 12 > 4. b < 4 or b > −2 b < 4 or b > 4 b < 4 or b > 2 b > 4 or b < −2
Solve each inequality and keep the word "or" in between them. \(6b < 24\) or \(4b + 12 > 4\) \(\dfrac{6b}{6} \lt \dfrac{24}{6} \) or \(4b + 12 -12 \gt 4 - 12\) \(b \lt 4\) or \(4b \gt -8 \) \(b \lt 4\) or \(\dfrac{4b}{4} \gt \dfrac{-8}{4} \) \(b \lt 4\) or \(b \gt -2\) Now look at the two inequalities. If b < 4 or b > -2, that means b can be any number. The solutions is all real numbers.
why dont you flip the sign
The sign in an inequality only flips direction when you multiply both sides or divide both sides by a negative number. In this case, we never did that.
For example: \(-5x \le 30 \) Here you need to divide both sides by -5, obviously a negative number, so you get this: \(\dfrac{-5x}{-5} \ge \dfrac{30}{-5} \) \(\dfrac{\cancel{-5}x}{\cancel{-5}1} \ge -6 \) \(x \ge -6 \)
the answer is A (b<4 or b>-2)
Yes, it's A.
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