To solve the inequality 5x + 15 < 10 + 20x, we first need to isolate x. We can start by rearranging the inequality:
1. Subtract 5x from both sides:
15 < 10 + 20x – 5x
2. This simplifies to:
15 < 10 + 15x
3. Next, subtract 10 from both sides:
15 – 10 < 15x
4. Which gives us:
5 < 15x
5. Now, divide both sides by 15:
&frac{5}{15} < x
6. Simplifying that gives:
&frac{1}{3} < x
This means that x must be greater than 1/3 for the inequality to hold.
So, all values greater than 1/3 are in the solution set of the inequality.