Solve this equation: 2x+8=0

Correct Answer: A

Rationale: In solving the equation 2x + 8 = 0, the correct answer is A) -4. To arrive at this solution, we need to isolate x by first subtracting 8 from both sides to get 2x = -8, then divide by 2 to find x = -4. Now, let's analyze the other options: B) 3: This answer is incorrect because if we substitute x=3 into the original equation, we get 2(3) + 8 = 6 + 8 = 14, not 0. C) 5: Similarly, substituting x=5 into the equation gives 2(5) + 8 = 10 + 8 = 18, which does not satisfy the equation. D) 0: Substituting x=0 gives 2(0) + 8 = 0 + 8 = 8, which also does not satisfy the equation. Educationally, this question assesses the test-taker's understanding of solving linear equations. It reinforces the importance of following the correct steps to isolate the variable and find the solution. Understanding these foundational concepts is crucial for success in more complex math problems and applications.

Correct Answer: C

Rationale: In this question, we are given the expression 5 + 2 x 2. To solve this expression, we need to follow the order of operations, which is parentheses, exponents, multiplication and division (from left to right), and addition and subtraction (from left to right), commonly remembered as PEMDAS. In this case, multiplication should be done before addition. So, we first multiply 2 and 2 to get 4. Therefore, the expression simplifies to 5 + 4. Adding 5 and 4 gives us 9. Now, let's analyze the answer choices: A) 1 - This is incorrect because we found the result to be 9, not 1. B) 2 - This is incorrect as well for the same reason mentioned above. C) 3 - This is the correct answer based on our calculations. D) 4 - This is incorrect because the result, as we calculated, is 9, not 4. Educationally, understanding the order of operations is crucial in math. It ensures that everyone arrives at the same answer when solving mathematical expressions. By following the order of operations, we can avoid confusion and errors in calculations. This question serves as a good reminder of the importance of correctly applying mathematical rules to arrive at the correct solution.

Correct Answer: C

Rationale: To find out how many days Bernard needs to work to make $300, we divide the total amount he needs by how much he makes per day: $300 / $80 = 3.75 days. Since Bernard can only work full days, he would need to work for 4 days to make $300. Therefore, the correct answer is 4 days. Choice A (2 days) is incorrect because it does not match the calculation based on his daily earnings. Choice B (3 days) is incorrect as the calculated result is not a whole number, so Bernard needs to work for more than 3 days. Choice D (5 days) is incorrect as it exceeds the calculated number of days needed to make $300.

Correct Answer: A

Rationale: The mean is calculated by summing all values in a dataset and then dividing by the total number of values. Outliers, which are data points significantly different from the other values, can greatly impact the mean because they affect the sum. The mean is sensitive to extreme values, making it the measure for the center of a small sample set most affected by outliers. The median, on the other hand, is not influenced by outliers as it represents the middle value when the data points are ordered. The mode is the value that appears most frequently in the dataset and is not directly influenced by outliers. Therefore, the correct answer is the mean, as it is highly influenced by outliers in a small sample set.

Correct Answer: A

Rationale: A line that travels from the bottom-left of a graph to the upper-right of the graph signifies a positive relationship between the predictor and dependent variable. This indicates that as the predictor variable increases, the dependent variable also increases. Choice B, 'Negative,' is incorrect as a negative relationship would be depicted by a line that travels from the top-left to the bottom-right of the graph. Choices C and D, 'Exponential' and 'Logarithmic,' respectively, represent specific types of relationships characterized by non-linear patterns, unlike the linear positive relationship shown in the described scenario.