PSAT/NMSQT flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Comma splice

Two independent clauses joined only by a comma. Fix with a period, semicolon, or comma plus a coordinating conjunction such as 'but' or 'so'.

Independent clause

A group of words containing a subject and a finite verb that can stand alone as a complete sentence, such as 'The experiment failed.'

Subordinating conjunction

A word like 'although', 'because', or 'while' that turns a clause into a dependent one, so it cannot stand alone as a sentence.

Semicolon use

Joins two closely related independent clauses without a conjunction, or separates items in a list that already contain commas.

Colon use

Follows an independent clause to introduce an explanation, list, or quotation; what precedes the colon must be a complete sentence.

Nonessential clause commas

A clause that adds extra but removable information is set off by commas on both sides; removing it should leave a grammatical sentence.

Subject-verb agreement

The verb must match its subject in number, ignoring phrases between them; 'the box of tools is' not 'are' on the table.

Pronoun-antecedent agreement

A pronoun must match its antecedent in number and person; singular antecedents take singular pronouns such as 'it' or 'its'.

Dangling modifier

An introductory phrase must describe the subject of the main clause; 'Walking home, the rain began' wrongly makes the rain walk.

Words in context

Questions asking which choice best fits the meaning of an underlined word; test each option in the full sentence and check the surrounding logic.

Command of evidence

Questions requiring a choice that directly supports or weakens a stated claim, often using data from a table or graph.

Text structure question

Asks how a passage or paragraph is organized, such as comparing two views, presenting a problem then a solution, or offering a counterexample.

Cross-text connections

Paired-passage questions asking how the authors' claims relate, whether they agree, disagree, or one qualifies the other's position.

Rhetorical synthesis

Questions that give bulleted notes and ask which sentence best accomplishes a stated goal, such as emphasizing a similarity.

Transition words

Words signaling logical relationships: 'however' for contrast, 'therefore' for conclusion, 'for example' for illustration, 'moreover' for addition.

Central idea

The main point a passage develops; the correct answer covers the whole passage rather than one supporting detail.

Inference question

Asks for a conclusion logically supported by the passage but not stated directly; the answer must follow from the text alone.

Slope formula

m = (y2 - y1)/(x2 - x1), the change in y divided by the change in x between two points on a line.

Slope-intercept form

y = mx + b, where m is the slope and b is the y-intercept, the y-value where the line crosses the y-axis.

Perpendicular line slopes

Two lines are perpendicular when their slopes are negative reciprocals, so their product equals -1.

Parallel line slopes

Two distinct lines are parallel when they have equal slopes and different y-intercepts, so they never intersect.

Quadratic formula

x = (-b plus or minus sqrt(b^2 - 4ac)) / (2a), giving the roots of ax^2 + bx + c = 0.

Discriminant

The expression b^2 - 4ac in a quadratic; positive means two real roots, zero means one, negative means none.

Vertex of a parabola

For y = ax^2 + bx + c, the vertex x-coordinate is -b/(2a); the vertex is the maximum or minimum point.

Exponential growth model

y = a(1 + r)^t, where a is the initial amount, r the growth rate per period, and t the number of periods.

Exponential decay model

y = a(1 - r)^t, where a is the initial amount and r the constant percent decrease per period.

Percent change

(new value - old value) / old value x 100; a positive result is an increase, a negative result a decrease.

Circle equation

(x - h)^2 + (y - k)^2 = r^2, a circle centered at (h, k) with radius r.

Special right triangles

In 30-60-90 triangles sides are in ratio 1 : sqrt3 : 2; in 45-45-90 triangles the ratio is 1 : 1 : sqrt2.

Trigonometric ratios

In a right triangle: sin = opposite/hypotenuse, cos = adjacent/hypotenuse, tan = opposite/adjacent for a given acute angle.

Mean versus median

The mean is the sum divided by the count and shifts with outliers; the median is the middle value and resists outliers.

Standard deviation

A measure of how spread out data values are around the mean; tightly clustered data have a small standard deviation.

Conditional probability

The probability of an event given that another occurred, computed from a two-way table by restricting the denominator to that row or column.