1 3 5 6

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1.

ANSWERS

INTERMEDIATE ALGEBRA

TEST CHAPTER 7

WEB SITE

1 x

3

5

2 y

4

7

2

= the exponents on the x are

2

3

1

-

2

5 6

=

2

5

+

2

=

11

2

4 the exponents on the y are

1

-

7

2

=

8

2

-

7

2

1

2

THE ANSWER TO THIS PROBLEM IS

11 1 x 2 y 2

2

2. 3

( 1 )(

1

)

3 x

(

2

1

)(

1

)

3 y

( 2 )(

3

1

)

= 3

1

3

1 x

6 y

2

3

= You can not have a negative exponent. THE

ANSWER TO THIS PROBLEM IS

1 x 6

1

2

3 3 y 3 x

3

2

4 7

= x

21

28

8

28

= x

29

28

3.

4.

7

6 x

3

5. Must have positive exponents in the answer.

1

1

=

1

4

or .25

64 3

In problems 6 – 9, find the prime factorization of the coefficients.

6. 40

(2)(2)(2)(5)

THE ANSWER IS

(2xy

3

)

3

5 x

2

7. 405

(3)(3)(3)(3)(5)

THE ANSWER IS

9x

3 y

4

5 xz

8. 27

(3)(3)(3)

THE ANSWER IS

(3xy

3

)

3 x

2

9. 16

5 x + 2 9

5 x - 3 4

5 x =

4

4

5 x

+ (2)(3)

4

5 x

- (3)(2)

5 x

=

5 x

+ 6

5 x

- 6

5 x

=

5 x

PAGE 2

10.

11.

Use FOIL to solve this problem.

2 9 + 8 6 - 5 6 - 20 4 = (2)(3) + 3 6 - (20)(2) = 6 + 3 6 - 40 = -34 + 3 6

You must multiply the denominator with a number and/or a letter to make the denominator a perfect square. YOU CAN NEVER HAVE A RADICAL(square root) IN THE

DENOMINATOR.

6

3 x

3 x

3 x

=

6 3

9 x

2 x

=

6 3

3 x x

=

2 denominator to reduce the fraction.) x

3 x

(You can divide 3 into the numerator and the

12.

3

7 x

=

3

7 x

3

3 x x

=

21 x

9 x

2

=

21 x

( You can not reduce this problem because the 21x is

3 x under the radical and the 3x is outside of the radical.)

13.

2

3

2

3

5

=

(

( 2

7 x

7

=

11

7

x =

11

7

3

2 )( 2

3

5 )( 2

3

5 )

3

5 )

= ( Use FOIL to multiply)

4

2 9

5

9

10

3

4

3

10

3

10

3

25

=

( 2 )(

(

3 )

4 )(

9

3 )

3

10

25

=

6

9

12

3

25

10

=

16

9

13

In problems 14 – 16, you must square both sides of the equation before solving the equations.

14. ( 7 x

5 )

2

= 4

2

15. (1 + x

1 )

2

= ( x

2 )

2

7x + 5 = 16

7x + 5 – 5 = 16 – 5

7x = 11

(1 +

1 + 1 x

1 )(1 + x

1 + 1 x

1 ) = x + 2 x

1 + x + 1 = x + 2

3

1 + 1 + x + 2

2 + x + 2 x x

1

1 = x + 2

= x + 2

2 – 2 + x – x + 2

2 x

1 = x – x + 2 – 2 x

1 = 0

2 x

1 0

=

2 2 x

1 = 0

( x

1 )

2

= 0

2

x + 1 = 0

x + 1 – 1 = 0 –1

x = -1

17.

16.

19.

20.

PAGE 3

(x – 3)

2

= ( 3 x

1 )

2

(x – 3)(x – 3) = 3x + 1 x

2

- 3x – 3x + 9 = 3x + 1 x

2

- 6x + 9 = 3x + 1 x

2

- 6x – 3x + 9 – 1 = 3x – 3x + 1 – 1 x

2

- 9x + 8 = 0 (factor the x

2

- 9x + 8)

(x – 1)(x – 8) = 0 ( set each equation to equal zero) x – 1 = 0 ; x – 8 = 0

x = 1 ; 8 (You need to check you answer to see if these numbers work in the problem.) i 16 = 4ị 18. (i 3 )(i 3 ) = ( i

2

)( 9 ) = 3ị to –1). Therefore 3ị

2

= -3

2

(We know that ị

2

is equal

Use FOIL to work problem. (4)(6) + (4)(2ị) + (6)(-3ị) + (-3ị)(2ị) = 24 + 8ị - 18ị - 6ị

2

14 - 10ị - (6)(-1) = 24 -10ị + 6 = 30 - 10ị

= ị = ị This pattern repeats. 4 units to this pattern, therefore 47

4 = 11 r 3. The remainder ị 2

= -1 is what we are interested in. Since the remainder is 3, ị

3

= -ị, therefor the answer to ị

3

= -ị this problem is -ị . ị 4

= 1

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