Equations in Two Variables

Vocabulary

100

The ratio of the vertical change to the horizontal change.

What is slope?

200

The vertical change.

What is Rise?

300

The horizontal change.

What is Run?

400

The y-coordinate of the point where a  line crosses the y-axis.

What is the y-intercept?

500

y = mx + b

What is slope intercept form?

Finding Slope

100

(0,1), (2,7)

What is 3?

200

(2,5),(3,1)

What is -4?

300

(1,2), (4, 7)

What is 5/3?

400

(-2,3), (7, -4)

What is -7/9?

500

(-6,-1), (4,1)

What is 1/5?

Point Slope Form

100

Passes through (1,9), slope = 2

y - 9 = 2(x - 1)

200

Passes through (4,1), slope = -3

y + 1 = -3(x - 4)

300

Passes through (-4,-5), slope = 3/4

y + 5 = 3/4(x + 4)

400

Passes through (3,-6) and (-1,2)

y + 6 = -2(x - 3)

500

Passes through (4,-4) and (8,-10)

y + 4 = -3/2(x - 4)

Slope Intercept Form

100

y = -5x + 2

m = -5

b = 2

200

y = 1/2x - 6

m = 1/2

b = -6

300

y = 3x + 4

m = 3

b = 4

400

3x + y = -4

m = -3

b = -4

500

y - 2x = 8

m = 2

b = 8

Solving Systems of Equations

100

y = x + 15

y = 2x

What is (15,30)?

200

y = 2x - 3

x + y = 18

What is (7,11)?

300

y = 1/4x

x + 4y = 8

What is (4,1)?

400

y = x + 12

4x + 2y = 27

What is (1/2, 25/2)?

500

10x + 3y = 19

y = 2x + 5

What is (1/4,11/2)?