Which of the following is the y-intercept of the line whose equation is 7y − 42x + 7 = 0?
- A. (1/6, 0)
- B. (6, 0)
- C. (0, −1)
- D. (−1, 0)
Correct Answer: C
Rationale: To find the y-intercept, set x = 0 in the equation 7y − 42x + 7 = 0. This simplifies to 7y - 42(0) + 7 = 0, which gives 7y = -7. Solving for y, we get y = -1. Therefore, the y-intercept is where x = 0, so the correct answer is (0, -1).
Choice A (1/6, 0) is incorrect as it does not satisfy the given equation when x = 0. Choice B (6, 0) is incorrect as it represents the x-intercept. Choice D (-1, 0) is incorrect as it does not correspond to the y-intercept of the given equation.
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What is the perimeter of a rectangle with a length of 12 cm and a width of 5 cm?
- A. 17 cm
- B. 24 cm
- C. 34 cm
- D. 40 cm
Correct Answer: C
Rationale: The correct formula for the perimeter of a rectangle is P = 2(l + w), where l represents the length and w represents the width. Substituting the given values into the formula: P = 2(12 cm + 5 cm) = 2(17 cm) = 34 cm. Therefore, the perimeter of the rectangle is 34 cm. Choice A (17 cm) is incorrect as it seems to have added only the length and width without multiplying by 2. Choice B (24 cm) is incorrect as it does not consider the multiplication by 2. Choice D (40 cm) is incorrect as it seems to have added the length and width without multiplying by 2.
Bridget is repainting her rectangular bedroom. Two walls measure 15 feet by 9 feet, and the other two measure 12.5 feet by 9 feet. One gallon of paint covers an average of 32 square meters. Which of the following is the number of gallons of paint that Bridget will use? (There are 3.28 feet in 1 meter.)
- A. 0.72 gallons
- B. 1.43 gallons
- C. 4.72 gallons
- D. 15.5 gallons
Correct Answer: B
Rationale: First, convert the dimensions to meters: 15 ft. (1 m/3.28 ft.) = 4.57 m; 9 ft. (1 m/3.28 ft.) = 2.74 m; 12.5 ft. (1 m/3.28 ft.) = 3.81 m. Next, find the total area in square meters: total area = 2(4.57 m 2.74 m) + 2(3.81 m 2.74 m) = 45.9 m². Finally, convert the area to gallons of paint: 45.9 m² (1 gallon/32 m²) = 1.43 gallons. Therefore, Bridget will need 1.43 gallons of paint to repaint her bedroom. Choices A, C, and D are incorrect because they do not accurately calculate the required amount of paint based on the given dimensions and the coverage area of one gallon of paint.
A car dealership's commercials claim that this year's models are 20% off the list price, plus they will pay the first 3 monthly payments. If a car is listed for $26,580, and the monthly payments are set at $250, what is the total potential savings?
- A. $1,282
- B. $5,566
- C. $6,066
- D. $20,514
Correct Answer: C
Rationale: To calculate the total potential savings: First, find the 20% discount on the list price of $26,580: 0.20 $26,580 = $5,316. Then, determine the savings over the first 3 months of payments: 3 months $250/month = $750. Add the discount and the monthly payment savings to get the total potential savings: $5,316 + $750 = $6,066. Therefore, the correct answer is $6,066. Choice A, $1,282, is incorrect because it does not account for the total savings from both the discount and the monthly payments. Choice B, $5,566, is incorrect as it miscalculates the total savings by excluding the savings from the monthly payments. Choice D, $20,514, is incorrect as it does not consider the discount and only focuses on the list price.
What is the result of the expression 102 - 7(3 - 4) - 25? Which of the following is correct?
- A. -12
- B. 2
- C. 68
- D. 82
Correct Answer: D
Rationale: To simplify the expression, we follow the order of operations (PEMDAS): Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right). First, solve inside the parentheses: 3 - 4 = -1. Then, multiply -1 by 7: -1 * 7 = -7. Now, substitute these values back into the expression: 102 - (-7) - 25 = 102 + 7 - 25 = 109 - 25 = 84. Therefore, the correct answer is 84. Choices A, B, and C are incorrect as they do not represent the correct simplification of the given expression.
Simplify the expression. What is the value of x? (5/4)x = 20
- A. 8
- B. 16
- C. 24
- D. 32
Correct Answer: D
Rationale: To solve for x, multiply both sides by the reciprocal of 5/4 to isolate x. (4/5)(5/4)x = (4/5)20; x = 16. Therefore, the correct answer is 32. Choice A (8), Choice B (16), and Choice C (24) are incorrect as they do not represent the correct value of x obtained after correctly simplifying the expression.