Tim solved the equation X + 7 = -15
When he checked back his solution didn’t work
What was his error?
“Grade” his paper and provide propped helpful feedback below. You can either include the steps to get the correct answer or describe what he did wrong
Tim's error was likely in the step where he transposed the constant term to the other side of the equation.
Here is the breakdown of the correct steps to solve the equation:
1. Start with the given equation: X + 7 = -15
2. To isolate the variable X, subtract 7 from both sides of the equation:
X + 7 - 7 = -15 - 7
X = -22
So, the correct solution is X = -22.
Feedback for Tim:
Tim, it seems like you made a mistake when transposing the constant term to the other side of the equation. Make sure to perform the same operation on both sides of the equation to maintain the equality. Additionally, double-check your calculations to avoid computational errors. Keep practicing and you'll improve!
To solve the equation X + 7 = -15, let's identify Tim's error.
To solve the equation, we need to isolate the variable X by moving the constant term (7) to the other side of the equation.
Here are the correct steps:
1. Start with the given equation: X + 7 = -15.
2. Subtract 7 from both sides of the equation to get rid of the constant term: X + 7 - 7 = -15 - 7.
Simplifying the left side: X = -15 - 7.
3. Simplify the right side: X = -22.
4. The value of X is -22.
Now, let's assess Tim's error:
Tim's error might have occurred when he tried to isolate the variable X. It seems like he didn't correctly subtract 7 from both sides of the equation. This mistake might have led to an incorrect solution.
Grade: C
Feedback: Your work shows that you attempted to solve the equation, but you made an error in the step where you tried to isolate X. When subtracting 7 from both sides, make sure to subtract 7 from the left side as well. Double-check your calculations to avoid mistakes. Keep practicing and you will improve!
To solve the equation X + 7 = -15, Tim needs to isolate the variable X on one side of the equation. Let's go through the steps to solve this equation correctly:
Step 1: Begin with the equation X + 7 = -15.
Step 2: Subtract 7 from both sides of the equation to isolate the variable X. This yields X = -15 - 7.
Step 3: Simplify the right side of the equation. -15 - 7 equals -22.
Therefore, the correct solution is X = -22.
Now, let's evaluate Tim's solution and provide feedback on his error:
Tim's approach was to subtract 7 from both sides of the equation to isolate X, as shown in the correct steps above. However, it seems that he made a mistake during this step or when simplifying the equation.
To grade Tim's paper, we can identify the error:
Tim's error: Tim incorrectly subtracted 7 from -15, resulting in X = -15 - 7 = -22.
Feedback: Tim's subtraction was correct in terms of arithmetic, but he made an error when simplifying the equation. The correct simplification would be -15 - 7 = -22, not -15 + 7 = -22. This is because subtracting a positive number is equivalent to adding its negative counterpart.
To help Tim, you should explain that when subtracting a positive number, it is important to remember to subtract its negative counterpart, rather than adding them together. Encourage him to double-check his simplification steps when solving equations to avoid similar errors in the future.