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Jet001 [13]
3 years ago
8

I need help with all 3 please

Mathematics
1 answer:
olganol [36]3 years ago
6 0

Step-by-step explanation:

x +2y = 9. .....(1)

x - 2y = 5. .....(2)

from eqn (1)

x + 2y = 9

x = 9 - 2y.

substitute x = 9 - 2y into eqn (2)

9 - 2y - 2y = 5

-4y = 5 - 9

-4y = -4

y = 1

sub y = 1 into eqn (1)

x + 2y = 9

x + 2(1) = 9

x + 2 = 9

x = 9 - 2

x = 7.

(2) x + y = 9 ....(1)

x - 2y = 0 .....(2)

from eqn (2)

x - 2y = 0

x =0 + 2y

substitute x = 2y into eqn (1)

x + y = 9

(2y) + y = 9

3y = 9

y = 3

substitute y = 3 into eqn (2)

x - 2y = 0

x - 2(3) = 0

x - 6 = 0

x = 6.

(3) 2x + 7y = 5. ....(1)

2x + 3y = 9. .....(2)

from eqn (1)

2x + 7y = 5

7y = 5 - 2x

y = (5 - 2x)/7

sub y = (5 - 2x)/7 into eqn (2)

2x + 3y = 9

2x + 3(5 - 2x)/7 = 9

2x + (15 - 6x)/7 = 9

multiply through by 7

14x + 15 - 6x = 63

14x - 6x = 63 - 15

8x = 48

x = 6

sub x = 6 into eqn (1)

2x + 7y = 5

2(6) + 7y = 5

12 + 7y = 5

7y = 5 - 12

7y = -7

y = -1

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On tuesday And wednesday , cab fare cost $7.75 total. On Monday and Thursday , cab Fare cost $6.30 on each day. On Friday , cab
Rashid [163]
The average daily cost is $7.02.
 
to get the average cost you add up all the prices

 7.75
 7.75
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+7.00
35.10

then you divide that by the amount of numbers you have

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then there's your answer.
7 0
3 years ago
Please help and thank you
ycow [4]

Answer:

D) 130 workers

Step-by-step explanation:

We have the equation, <em>y = 2x + 40</em>, and <em>y, 300</em> (since the y-coordinate represents the # of bottles made), so we can solve for x, <em>the number of workers needed</em>.

Substitute: <em>300 = 2x + 40</em>

Subtract: <em>260 = 2x</em>

Divide: <em>x = 130</em>

Since x = 130 when y = 300, 130 workers are required to make 300 bottles in a day.

4 0
3 years ago
When a snozzberry marmalade machine works at 100% of its capacity, it can make 500 jars of snozzberry marmalade per hour. How ma
Amiraneli [1.4K]

Answer:

350

Step-by-step explanation:

500*70%=350

3 0
3 years ago
A leading magazine (like Barron's) reported at one time that the average number of weeks an individual is unemployed is 27 weeks
miss Akunina [59]

Answer:

X ~ N(27, 4) ;

xbar ~ N(27, 0.1026) ;

0.5 ;

0.5

Step-by-step explanation:

Probability distribution of X : N(μ, σ²)

μ = 27 ; σ = 2

X ~ N(μ, σ²) = X ~ N(27, 2²) ;X ~ N(27, 4)

Distribution is approximately normal ; μ = xbar ; xbar = 27

(Standard Error)² = (σ/√n)²= (2/√39)² = 0.1026

xbar ~ N(μ, σ²) = xbar ~ N(27, 2²) ; xbar ~ N(27, 0.1026)

Probability that a randomly selected individual found a job in less than 27 weeks :

P(X < 27) :

Obtain the Zscore :

Z = (x - μ) / σ

Z = (27 - 27) / 2 = 0/2

Z = 0

P(Z < 0) = 0.5

D.) n = 36

P(X < 27) :

Obtain the Zscore :

Z = (x - μ) / σ/√n

Z = (27 - 27) / (2/√36) = 0/0.33333

Z = 0

P(Z < 0) = 0.5

7 0
3 years ago
On a piece of paper, use a protractor to construct a triangle with angle measures of 40° and 60º.
Triss [41]
All 3 triangle angles sum to 180 degrees.
So third angle = 180 -40 -60
third angle = 80 degrees

6 0
3 years ago
Read 2 more answers
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