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velikii [3]
3 years ago
14

Expand (3x+7)(3x-7) =

Mathematics
2 answers:
saveliy_v [14]3 years ago
8 0

Answer:

9 {x}^{2}  - 49

Step-by-step explanation:

Do FOIL, first outside inside last

3x × 3x = 9x^2

3x × -7 = -21x

7 × 3x = 21x

7 × -7 = -49

9 {x}^{2}   - 21x + 21x - 49 \: midde \: cancels \: each \: other \: out

So it would just be 9x^2 - 49

Tamiku [17]3 years ago
8 0

(3x + 7)(3x - 7) =

= 9x² + 21x - 21x - 49

= 9x² - 49

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The following is a linear programming formulation of a labor planning problem. There are four overlapping shifts, and management
dexar [7]

Answer:

d. 15

Step-by-step explanation:

Putting the values in the shift 2 function

X1 + X2 ≥ 15

where x1=  13, and x2=2

13+12≥ 15

15≥ 15

At least 15 workers must be assigned to the shift 2.

The LP model questions require that the constraints are satisfied.

The constraint for the shift 2 is that the  number of workers must be equal or greater than 15

This can be solved using other constraint functions e.g

Putting  X4= 0 in

X1 + X4 ≥ 12

gives

X1 ≥ 12

Now Putting the value X1 ≥ 12  in shift 2 constraint

X1 + X2 ≥ 15

12+ 2≥ 15

14 ≥ 15

this does not satisfy the condition so this is wrong.

Now from

X2 + X3 ≥ 16

Putting X3= 14

X2 + 14 ≥ 16

gives

X2  ≥ 2

Putting these in the shift 2

X1 + X2 ≥ 15

13+2 ≥ 15

15 ≥ 15

Which gives the same result as above.

6 0
3 years ago
Alesha went to the movies. A popcorn is $3 more than a soda. She purchased 1 popcorn and 2 sodas. She spent $21. How much is a p
Blizzard [7]

Answer: a popcorn is $9

Step-by-step explanation:

soda is $6

8 0
2 years ago
Luis earns a base salary of $150.00 every week with an additional 14% commission on everything he sells. If Luis sold $6,050.00
max2010maxim [7]
Luis earns a solid $150 and that doesn't change, now you need to calculate 14% of $6,050. 
x=150+(0.14x6050)
    150+(847)
    997
Luis was paid $997.
3 0
4 years ago
Read 2 more answers
Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.
Anna007 [38]

Answer:

  yes; 1.25

Step-by-step explanation:

The length to width ratios of the rectangles are ...

  A: 12/8 = 1.5

  B: 15/10 = 1.5

  C: 30/15 = 2.0

__

Rectangles A and B have the same aspect ratio, so are similar. Rectangle B is a scaled copy of A with a scale factor of 10/8 = 1.25.

7 0
4 years ago
Please factor 5x^2-23x+12
STALIN [3.7K]

5x^2-23x+12

= 5x^2 - 20x - 3x +  12

= 5x(x - 4) - 3(x - 4)

= (5x - 3)(x - 4)

Hope that helps

3 0
3 years ago
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