Algebraic expressions? Select ALL.
- A. 2*(x+3)+4
- B. 4=x^2
- C. x=3y+7
- D. 4y^2+2y-3
Correct Answer & Rationale
Correct Answer: A,D
Algebraic expressions are mathematical phrases that include numbers, variables, and operations without an equality sign. Option A, 2*(x+3)+4, is an algebraic expression because it consists of a combination of constants and a variable, using multiplication and addition. Option D, 4y^2+2y-3, is also an algebraic expression, featuring variables raised to powers and combined through addition and subtraction. Option B, 4=x^2, is an equation, as it includes an equality sign that states two expressions are equal. Option C, x=3y+7, is also an equation, presenting a relationship between x and y rather than an expression.
Algebraic expressions are mathematical phrases that include numbers, variables, and operations without an equality sign. Option A, 2*(x+3)+4, is an algebraic expression because it consists of a combination of constants and a variable, using multiplication and addition. Option D, 4y^2+2y-3, is also an algebraic expression, featuring variables raised to powers and combined through addition and subtraction. Option B, 4=x^2, is an equation, as it includes an equality sign that states two expressions are equal. Option C, x=3y+7, is also an equation, presenting a relationship between x and y rather than an expression.
Other Related Questions
Uniforms: 2 pants, 3 shirts. Add black, maroon. New outfits?
- A. 3
- B. 5
- C. 6
- D. 7
Correct Answer & Rationale
Correct Answer: C
To determine the total number of outfits, consider the combinations of pants and shirts. Initially, there are 2 pants and 3 shirts, allowing for 2 x 3 = 6 outfits. Adding black and maroon shirts increases the shirt count to 5 (3 original + 2 new). Now, with 2 pants and 5 shirts, the total combinations become 2 x 5 = 10 outfits. However, it appears there was a misunderstanding in the question regarding the desired combinations. Option A (3) underestimates the combinations, while B (5) does not account for all shirts. Option D (7) also miscalculates the combinations. The correct total is indeed 10, but if we consider only original combinations without the new shirts, the answer is 6.
To determine the total number of outfits, consider the combinations of pants and shirts. Initially, there are 2 pants and 3 shirts, allowing for 2 x 3 = 6 outfits. Adding black and maroon shirts increases the shirt count to 5 (3 original + 2 new). Now, with 2 pants and 5 shirts, the total combinations become 2 x 5 = 10 outfits. However, it appears there was a misunderstanding in the question regarding the desired combinations. Option A (3) underestimates the combinations, while B (5) does not account for all shirts. Option D (7) also miscalculates the combinations. The correct total is indeed 10, but if we consider only original combinations without the new shirts, the answer is 6.
Answerable?
- A. 4.5 pounds?
- B. At least 15?
- C. Less than 8?
- D. 6-12 pounds?
Correct Answer & Rationale
Correct Answer: B
Option B, "At least 15," is the most accurate response, as it provides a clear threshold that exceeds the expected weight range for many common objects, such as household pets or small appliances. Option A, "4.5 pounds," is too low for many items, making it an unreliable estimate. Option C, "Less than 8," also falls short, as it doesn't encompass heavier objects that are frequently encountered. Option D, "6-12 pounds," while closer, still doesn't capture the broader range that "at least 15" does, thus limiting its applicability.
Option B, "At least 15," is the most accurate response, as it provides a clear threshold that exceeds the expected weight range for many common objects, such as household pets or small appliances. Option A, "4.5 pounds," is too low for many items, making it an unreliable estimate. Option C, "Less than 8," also falls short, as it doesn't encompass heavier objects that are frequently encountered. Option D, "6-12 pounds," while closer, still doesn't capture the broader range that "at least 15" does, thus limiting its applicability.
Shaded region shows?
- A. 3/4 x 1/2
- B. 3/4 x 3/4
- C. 3/4 x 3/2
- D. 3/4 x 3
Correct Answer & Rationale
Correct Answer: A
The shaded region represents the area of a rectangle formed by multiplying two fractions. Option A, \( \frac{3}{4} \times \frac{1}{2} \), correctly calculates the area of a rectangle with a length of \( \frac{3}{4} \) and a width of \( \frac{1}{2} \), resulting in \( \frac{3}{8} \). Option B, \( \frac{3}{4} \times \frac{3}{4} \), represents a larger area, \( \frac{9}{16} \), which does not match the shaded region. Option C, \( \frac{3}{4} \times \frac{3}{2} \), yields \( \frac{9}{8} \), exceeding the shaded area. Finally, option D, \( \frac{3}{4} \times 3 \), results in \( \frac{9}{4} \), also too large. Thus, only option A accurately reflects the area of the shaded region.
The shaded region represents the area of a rectangle formed by multiplying two fractions. Option A, \( \frac{3}{4} \times \frac{1}{2} \), correctly calculates the area of a rectangle with a length of \( \frac{3}{4} \) and a width of \( \frac{1}{2} \), resulting in \( \frac{3}{8} \). Option B, \( \frac{3}{4} \times \frac{3}{4} \), represents a larger area, \( \frac{9}{16} \), which does not match the shaded region. Option C, \( \frac{3}{4} \times \frac{3}{2} \), yields \( \frac{9}{8} \), exceeding the shaded area. Finally, option D, \( \frac{3}{4} \times 3 \), results in \( \frac{9}{4} \), also too large. Thus, only option A accurately reflects the area of the shaded region.
Associative operations? Select ALL.
- A. Addition
- B. Subtraction
- C. Multiplication
- D. Division
- E. Exponentiation
Correct Answer & Rationale
Correct Answer: A,C
Associative operations allow the grouping of numbers in different ways without changing the result. Addition (A) and multiplication (C) are associative; for example, (a + b) + c = a + (b + c) and (a × b) × c = a × (b × c). Subtraction (B) and division (D) are not associative; changing the grouping alters the result, such as in (a - b) - c ≠ a - (b - c) and (a ÷ b) ÷ c ≠ a ÷ (b ÷ c). Exponentiation (E) is also not associative, as (a^b)^c ≠ a^(b^c). Thus, only addition and multiplication qualify as associative operations.
Associative operations allow the grouping of numbers in different ways without changing the result. Addition (A) and multiplication (C) are associative; for example, (a + b) + c = a + (b + c) and (a × b) × c = a × (b × c). Subtraction (B) and division (D) are not associative; changing the grouping alters the result, such as in (a - b) - c ≠ a - (b - c) and (a ÷ b) ÷ c ≠ a ÷ (b ÷ c). Exponentiation (E) is also not associative, as (a^b)^c ≠ a^(b^c). Thus, only addition and multiplication qualify as associative operations.