CSET Mathematics: Number Theory and Algebra Flashcards

Which of the following best describes a rational number?

Answer: Any number that can be written as p/q where p and q are integers and q ≠ 0

A rational number is any number expressible as the ratio p/q of two integers where the denominator is not zero.

What is the slope of a line perpendicular to y = (2/3)x + 5?

Answer: −3/2

Perpendicular lines have slopes that are negative reciprocals; the negative reciprocal of 2/3 is −3/2.

Which of the following is an example of the associative property of addition?

Answer: (a + b) + c = a + (b + c)

The associative property states that grouping of addends does not change the sum: (a + b) + c = a + (b + c).

Solve for x: 3(x − 4) = 2x + 7

Answer: x = 19

3x − 12 = 2x + 7, so x = 19.

What is the degree of the polynomial 4x³ − 7x² + x − 9?

Answer: 3

The degree of a polynomial is the highest exponent of the variable, which is 3 here.

Which of the following correctly factors x² − 9?

Answer: (x − 3)(x + 3)

x² − 9 is a difference of two squares: x² − 3² = (x − 3)(x + 3).