Page 486 - Algebra 1

The table shows the number of people employed in agriculture in the United States from the year 1940 to the year 2000.
Year
1940
1950
1960
1970
1980
1990
2000
Employment (in millions)
9.5
7.2
5.5
3.5
3.4
3.2
2.5
k.
(Ex 5)
l.
(Ex 5)
m.
(Ex 5)
n.
(Ex 5)
U. S. Agricultural Employment
Draw a scatter plot and a trend line for the data.
Use the trend line to make a prediction for the population in the year 2010.
Find the equation for a line of best fit using a graphing calculator. Round the values for a and b to the nearest thousandth.
Use the equation for the line of best fit to estimate the population in the year 2010. Round the answer to the nearest half million.
Practice
Distributed and Integrated
x
1
2
3
4
5
6
y
26
24
21
14
9
5
1. Make a scatter plot from the data in the table. (71)
Is the ordered pair (5, 2) a solution to the following systems?
2. y=7-x
(55)
y y = = _ _1 1 x x + + 1 1
5
Subtract.
4. 31√ 5 - 13√5
(69)
3.5y-x=5
(55)
y y = = 2 2 x x - - 8 8
*5. √ 27 - √ 12 (69)
Find the common solution for each system of equations.
6. -y=x+8
(67)
y y = = - - x x + + 1 1
*7. 6y-x=12
(67)
Write an inverse variation equation relating x and y.
8. x=_2,y=33 9. x=6,y=14
*10. Error Analysis Two students solved the inequality 14 < -0.2k as shown below. (70) Which student is correct? Explain the error.
(64) 3 (64)
y y = = _ _1 1 x x + + 2 2 6
Student A
14 < -0.2k -0.2
_ 0.2 -0.2
_14> k
70 > k
Student B
_14 < -0.2k
14
-0.2 > -0.2k
-70 > k
-0.2 _
Lesson 71 471