To determine the correct method for solving an equation, we usually want to isolate the variable by performing operations that maintain the equality of both sides.
Let's denote the equation as \(3x = 15 + 30\). Here's how each choice works out:
A. Divide both sides of the equation by 3, and then add 15 to both sides.
- This is not correct. If you divide both sides by 3 first, you cannot then simply add 15 to both sides without changing the value of the equation incorrectly.
B. Divide both sides of the equation by 3, and then subtract 30 from both sides.
- This does not correctly isolate the variable in step one, as you subtracting after division could lead to confusion and is not standard practice.
C. Add 15 to both sides of the equation, and then divide both sides by 3.
- This is correct! By adding 15 first, you can then correctly isolate the variable after.
D. Subtract 15 from both sides of the equation, and then divide both sides by 3.
- This isn't the right approach if your goal was simply to isolate the variable, as you first reduce the equation, and dividing wouldn't yield the original purpose efficiently.
The best choice for solving the equation correctly among the options is:
C. Add 15 to both sides of the equation, and then divide both sides by 3.