Question

Which expression has a value that is equivalent to the given expression when n = 8?

Answer 1

Q1.

Put the value of n = 8 to the expressions:

2n + 10 → 2(8) + 10 = 16 + 10 = 26

A: 3n → 3(8) = 24 ≠ 26

B: 2(n + 5) → 2(8 + 5) = 2(13) = 26   :)

C: n² + 5 → 8² + 5 = 64 + 5 = 69 ≠ 26

D: 10n + 2 → 10(8) + 2 = 80 + 2 = 82 ≠ 26

Answer: B: 2(n + 5)

Q2.

x = 3, y = 2

L = 5y² - 2x → L = 5(2)² - 2(3) = 5(4) - 6 = 20 - 6 = 14

R = x² + ... → R = 3² + ... = 9 + ...

A: x² + x → 9 + 3 = 12  NOT

B: x² + y → 9 + 2 = 11   NOT

C: xy → 9 + (3)(2) = 9 + 6 = 15 YES

D: 2y → 9 + (2)(2) = 9 + 4 = 13   NOT

5y² - 2x < x² + xy

L = 14, R = 15, L < R    CORRECT

Answer: C: xy

Q3.

3 + 6² = 3 + 36 = 39

A: 3³ + 12 = 27 + 12 = 39  NOT

B: 5² + 4² = 25 + 16 = 41 > 39    YES

C: 2³ + 5² + 6 = 8 + 25 + 6 = 39    NOT

D: 2³ + 14 + 17 = 8 + 14 + 17 = 39    NOT

Answer: B: 3 + 6² < 5² + 4²