Download 1_2

1.2 Linear Equations
1
1
Solve the equation:  x  1  3   3 x  2 
3
4
1

1

12   x  1  3  12   3x  2  
3

4

4  x 1  3 12  3  3x  2
4x  4  36  9x  6
4x  40  9x  6
5x  46
4x  40  40  9x  9x  6  40  9x
5 x 46

5 5
46
x
5
Solve the equation:  3x 1 x  2   x  33x  2
3x 2  5 x  2  3x 2  7 x  6
5x  2  7 x  6
5x  7 x  4
2x  4
x2
2
3
1
Solve the equation:


x  1 x  3  x  3 x  1
 3

2
1
  x  3 x  1 

 x  3 x  1

x 1
 x  3  x  3 x  1 
2 x  6  3  x  1  1
 x  8
2x  6  3x  3  1
x 8
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall.
3x
6
Solve the equation:
1 
x2
x2
 3x

 6 
 1  x  2   

  x  2 ,
 x2 
 x2
x2
3x  x  2  6
4x  2  6
4x  8
x2
no solution
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall.
In the United States we measure temperature in both
degrees Fahrenheit (F) and degrees Celsius (C).
5
They are related by the formula C   F  32  .
9
What are the Fahrenheit temperatures corresponding to
Celsius temperatures of  10, 0, and 40 ?
9C  5  F  32 
9C  5F 160
9
F  C  32
5
9C 160  5F
9
F  C  32
5
9
For  10: F  (10)  32  14F
5
9
For 0: F  (0)  32  32F
5
9
For 40: F  (40)  32  104F
5
A total of $16,000 is invested, some in stocks and some in bonds.
If the amount invested in bonds is one fourth that invested in
stocks, how much is invested in each category?
We also know that:
Total amount invest in bonds is one fourth that in stocks
1
16, 000  x
x
4

x =12,800
So $12,800 is invested in stocks and $16,000 – $12,800 = $3,200
is invested in bonds.
Andy grossed $440 one week by working 50 hours. His employer
pays time-and-a-half for all hours worked in excess of 40 hours.
What is Andy’s hourly wage?
The sum of regular salary plus overtime salary will equal $440.
From the table, 40x + 15x = 440.
x =8
Andy’s regularly wage is $8.00 per hour.
A)
B)
C)
D)