Math 0094

Review Test 3

Solutions

  1. Subtract the given polynomials:

 

  1. Add the following polynomials:

 

  1. Multiply the following polynomials:

(3x-8y)(4x + 2y)          Use FOIL

  1. Multiply the following polynomials:       

  1. Multiply

Rewrite as (3x – 2)(3x – 2) and then use FOIL:

  1. Divide the following:

Divide each term in the numerator by the denominator:

 

 

 

 

 

  1. Divide the following:

Rewrite as a long division problem:  Put a zero in for any missing terms.

  1. Divide the following:
  2. Simplify the following: :

Anything to the zero power is 1.

 

  1. Simplify the following:

  1. Simplify the following:

16x^4 y^12

  1. Put the following number in scientific notation.  93,000,000

9.3(10)^7

  1. Put the following number in scientific notation: 0.000 000 0037

3.7(10)^-9

  1. If the sun is 9.3(10^7) miles from the earth and light travels at 1.86(10)^5 miles per second, how long will it take light to reach the earth from the sun?

Distance = Rate x Time

=

= 5(10)^2

= 500 seconds or 8 minutes and 20 seconds

  1. Factor the following completely:

 

    1. factor by grouping since there are 4 terms

Neither term factors further so we are done.

    1.            Factors of 3 are 1 and 3.  Factors of 24 are 1,24:      

2,12: 3,8:4,6                

Note that 3 can’t pair with anything divisible by 3

such as 24, 12, 3, or 6.

(3x+2)(x-12)

 

Prime

    1. GCF

       difference of two squares

9(3x + 1)(3x – 1)

    1.        difference of two cubes

    1.       The sum of perfect cubes.

  1. Find all possible values of k for which the following will factor over the integers.

            k=

(8x +1)(x-9)                 -71

(8x – 1)(x + 9)             71

(8x + 9)(x –1)              1

(8x –9)(x + 1)              -1

(8x + 3)(x – 3)             -21

(8x – 3)(x +3)              21

(4x +1)(2x – 9)            -34

(4x-1)(2x + 9)              34

(4x + 9)(2x –1)            14

(4x –9)( 2x +1)            -14

(4x+3)(2x-3)                -6

(4x – 3)(2x + 3)           6

The column on the right represents possible values of k.

  1. Use the area of rectangles to multiply (3x + 2)(2x +5)

6x^2

 

4x

 
3x        +2

2x

 

 


+5

The product of the length and width is the area.  This will be the sum of the 4 interior rectangles.  Therefore (3x + 2)(2x +5) = 6x^2 + 4x + 15x +10 or 6x^2 +19x + 10.