Sections 2.2, 2.3, & 2.5

x-Intercept vs. y-Intercept

100

The y-intercept of y = x + 2

2 or (0,2)

200

The x-intercept of y = x + 2

-2 or (-2,0)

300

The y-intercept of y = -x² + 4

4 or (0,4)

400

The x-intercept of y = 3x - 9

3 or (3,0)

500

The x-intercepts of 4x² + y = 4

-1 & 1 or (-1, 0) & (1, 0)

Symmetric How?

100

See #41 in the e-Textbook. (p.167)

x-axis, y-axis, & origin symmetry

200

See #43 in the e-Textbook. (p.167)

y-axis symmetry

300

See #45 in the e-Textbook. (p.167)

x-axis symmetry

400

See #47 in the e-Textbook. (p.167)

origin symmetry

500

See #49 in the e-Textbook. (p.167)

no symmetry

Which form?

100

What form is the equation y-2 = 3(x+4) in?

Point-slope

200

What form is the equation y = 2x + 3 in?

Slope-intercept

300

What form is the equation -x + 3y = 6 in?

General

400

What form is the equation y-1/2 = 2(x+3/4) in?

Point-slope

500

What form is the equation (1/2)y = x - 1 in?

It isn't.

Parallel or Perpendicular

100

y = 2x - 3

y = 2x + 4

Parallel

200

y = 4x + 7

y = -1/4x - 2

Perpendicular

300

y = 4x + 5

y = -4x + 2

Neither

400

y = 5x + 10

y = 1/5x - 3

Neither

500

-6x + y = 1

-1/3 = 2x - 1/3y

Same

Direct vs. Inverse Variation

100

y = k/x

Inverse variation

200

y = kx

Direct variation

300

Formula for when y varies directly with x; with y = 2 when x = 10

y = (1/5)x

400

Formula for when y varies inversely with sqrt(x); with y = 4 when x = 9

y = 12/sqrt(x)

500

Formula for when M varies directly with the square of d and inversely with the square root of x; with M = 24 when x = 9 and d = 4.

M = (9d^2)/(2sqrt(x))