GED Mathematical Reasoning Algebra and Functions 5

Question 1

What is the domain of the function f(x) = √(x - 4)?

Accepted Answer

x ≥ 4

Answer

The expression under the radical must be ≥ 0, so x - 4 ≥ 0, meaning x ≥ 4.

Question 2

Factor completely: 2x² + 8x

Accepted Answer

2x(x + 4)

Answer

The GCF of 2x² and 8x is 2x, so 2x² + 8x = 2x(x + 4).

Question 3

A store sells T-shirts for $12 each plus a one-time shipping fee of $5. Which equation models the total cost T for n shirts?

Accepted Answer

T = 12n + 5

Answer

Each shirt costs $12 (variable) plus a flat $5 shipping, so T = 12n + 5.

Question 4

Which of the following represents an exponential growth function?

Accepted Answer

y = 3(2)ˣ

Answer

Exponential functions have the variable in the exponent with a base greater than 1, like y = 3(2)ˣ.

Question 5

Solve for x: (x/3) + 5 = 9

Accepted Answer

x = 12

Answer

x/3 = 4, so x = 12.

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