Nokea
Solve this equation:
2x+8=0
- A. -4
- B. 3
- C. 5
Correct Answer: A
Rationale: To solve
2
x
+
8
=
0
2x+8=0:
Subtract 8 from both sides:
2
x
=
−
8
2x=−8
Divide both sides by 2:
x
=
−
8
2
=
−
4
x=
2
−8
​
=−4
Therefore, the solution is
x
=
−
4
x=−4.
You may also like to solve these questions
How much did he save from the original price?
- A. $170
- B. $212.50
- C. $105.75
- D. $200
Correct Answer: B
Rationale: To calculate the amount saved from the original price, you need to subtract the discounted price from the original price. The formula is: Original price - Discounted price = Amount saved. In this case, the original price was $850, and the discounted price was $637.50. Therefore, $850 - $637.50 = $212.50. Hence, he saved $212.50 from the original price. Choice A ($170) is incorrect as it is not the correct amount saved. Choice C ($105.75) is incorrect as it does not match the calculated savings. Choice D ($200) is incorrect as it is not the accurate amount saved based on the given prices.
What is the value of b in this equation? 5b - 4 = 2b + 17
- A. 13
- B. 24
- C. 7
- D. 21
Correct Answer: C
Rationale: To find the value of b in the equation 5b - 4 = 2b + 17, you need to first simplify the equation. By subtracting 2b from both sides of the equation and adding 4 to both sides, you get 3b = 21. Then, dividing both sides of the equation by 3 gives you b = 7. Therefore, the value of b is 7, which corresponds to option C. Choice A (13) is incorrect as it does not match the correct calculation. Choice B (24) is incorrect as it is not the result of the correct algebraic manipulation. Choice D (21) is incorrect as it is not the value of b obtained after solving the equation step by step.
A student gets an 85% on a test with 20 questions. How many answers did the student solve correctly?
- A. 15
- B. 16
- C. 17
- D. 18
Correct Answer: C
Rationale: To determine the number of questions the student solved correctly, we need to calculate 85% of the total number of questions. This can be done by multiplying the total number of questions by 85%, which is 20 questions x 85% = 20 x 0.85 = 17 questions. Therefore, the student solved 17 questions correctly. Choice A, 15, is incorrect as it does not reflect the correct percentage of questions solved. Choice B, 16, and Choice D, 18, are also incorrect as they do not match the calculation based on the given percentage.
The value of 6 x 12 is the same as:
- A. 2 x 4 x 4 x 2
- B. 7 x 4 x 3
- C. 6 x 6 x 3
- D. 3 x 3 x 4 x 2
Correct Answer: A
Rationale: To find the value of 6 x 12, we multiply 6 by 12, which equals 72.
A: 2 x 4 x 4 x 2 = 32
B: 7 x 4 x 3 = 84
C: 6 x 6 x 3 = 108
D: 3 x 3 x 4 x 2 = 72
Therefore, the correct answer is A, as the product of 2 x 4 x 4 x 2 equals 32, which is the same as 6 x 12.
When rounding 2678 to the nearest thousandth, which place value would be used to decide whether to round up or round down?
- A. Ten-thousandth
- B. Thousandth
- C. Hundredth
- D. Thousand
Correct Answer: B
Rationale: When rounding 2678 to the nearest thousandth, you would look at the digit in the thousandth place, which is 7. To decide whether to round up or down, you consider the digit to the immediate right of the place you are rounding to. Since 7 is equal to or greater than 5, you round up. Choice A, ten-thousandth, is incorrect as we are rounding to the thousandth place. Choice C, hundredth, is not relevant as we are not rounding to that place value. Choice D, thousand, is incorrect as it is the original number being rounded, not the place value used for rounding.