Q 01/05

Slope is defined as rise over what?

A) Rise

B) Run

C) Length

D) Height

Answer · why

B) Run

It is usually written m; a line that goes up from left to right has positive slope.

Q 02/05

What is the slope of the line through the points (1, 2) and (3, 8)?

A) 4

B) 6

C) 12

D) 3

Answer · why

D) 3

Rise is 8 − 2 = 6 and run is 3 − 1 = 2, so the slope is 6/2 = 3.

Q 03/05

Which letter is traditionally used for slope in the equation y = mx + b?

A) b

B) x

C) m

D) y

Answer · why

C) m

Nobody is sure why; it first appears in English in O'Brien's 1844 textbook.

Q 04/05

What does a line with positive slope do as you read it from left to right?

A) It goes up

B) It goes down

C) It stays level

D) It goes straight up

Answer · why

A) It goes up

A larger absolute value of slope means a steeper line.

Q 05/05

Where does the graph of y = 2x − 5 cross the y-axis?

A) At (0, 2)

B) At (5, 0)

C) At (0, −5)

D) At (−5, 0)

Answer · why

C) At (0, −5)

Set x = 0 and you get y = −5; the y-intercept is the constant term in slope-intercept form.