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When evaluating expressions, you follow a specific order to simplify them. The standard order is parentheses first, then exponents (if any), followed by multiplication and division from left to right, and finally addition and subtraction from left to right. This is often remembered by the acronym PEMDAS.
To evaluate an expression, carefully attend to each part of it. If the expression contains parentheses, start by simplifying what’s inside them. Then proceed with the rest of the steps accordingly.
In the exercise, we first had to simplify inside the parentheses, which contained -3 and -7. By adding them, we obtained -10. After that, we moved on to multiplying the result by 5 to get the final answer.

Negative numbers can sometimes be tricky, but they follow straightforward rules. When adding negative numbers, consider the direction on a number line, moving further away from zero.
For example, adding -3 and -7 involves moving 3 units to the left from zero and then an additional 7 units to the left. The result is -10. This is because both numbers are negative, and their absolute values (3 and 7) are combined while keeping the negative sign.
When multiplying a negative number, the rules are:

• A positive number times a negative number is always negative.
• A negative number times a negative number is always positive.
• A negative number times zero is zero.

In the exercise, multiplying 5 by -10 followed the rule of a positive number times a negative number resulting in a negative product, which gave us -50.

Simplifying inside parentheses is the first step in evaluating an expression and follows the PEMDAS rule. Parentheses help group parts of an expression to be solved first, ensuring accurate results.
In our given problem, the expression inside the parentheses was -3 - 7. We simplified this part first by adding -3 and -7 together to get -10. This made the problem simpler for the next steps.
Ignoring parentheses can lead to incorrect results, so always ensure to deal with them initially. Once the content within parentheses is simplified, you can proceed confidently to the remaining parts of the expression.