Equations Of Lines Curve Fitting (Page 3 of 3) in pdf

Equations Of Lines Curve Fitting Page 3

V. Summary of Linear Equations (p. 232)

General Equation Characteristics of Equation

Standard form where A is positive and A ≠ 0 and B ≠ 0,

Ax + By = C

−

x-intercept = (

, 0) , y-intercept = (0,

) slope =

x = a

Vertical line with x-intercept of ( a, 0), no y-intercept,

slope is undefined

y = b

Horizontal line with y-intercept of (0, b ), no x-intercept,

slope = 0

y = mx + b

Slope-intercept form with y-intercept of (0, b ), slope = m

y – y

= m(x – x

) Point-slope form that contains (x

, y

), slope = m

VI. Applications of Linear Equations (pp. 232 – 235)

Ex. The following table lists the total federal debt in 1985 and 1989.

Year Federal Debt

Use 1985 as x = 0.

1985 1828 billion

1989 2881 billion

Equation describing data: _______________________________

Using this equation, what was the debt in 1984? ____________________

Using this equation, what was the debt in 1990? ____________________

*Your instructor may show you another method using your calculator (STAT) and linear regression

to write an equation of a line when given many points of information.

Assignment:

pp. 236 – 241 #1 – 4, 5 – 25 odd, 26, 35 – 41 odd, 47ac

Equations Of Lines Curve Fitting Page 3