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3 years ago

Which ordered pair is the solution to the system of equations?

1 answer:

7 0

X+y=-1
x-3y=11
------------- (subtract equation)
4y = -12
y = -12/4
y= -3
-------------- (substitute y)

x-3=-1
x=-1+3
x=2

Answer ----> A (2,-3)

-5x-3y=12
x-3y=-6

you want to multiply the top equation by -1 to swap the signs and make the x's positive like the bottom equation

5x+3y=-12
x-3y=-6

then you have to multiply every value in the bottom equation by 5 so you are able to subtract it from the top equation

5x+3y=-12
5x-15y=-30
---------------- (subtract)
18y=18
y=18/18
y=1
------------------ (substitute y)
x-3=-6
x=-6+3
x=-3

answer = (-3,1)

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amm1812

Answer:

6:59

Step-by-step explanation:

Hour : Minute

Small hand is hour hand, large hand is minute hand. Minutes go by the small tic marks, where the hours go off of the numbers.

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3 years ago

Read 2 more answers

Waiting Line Models:Movies tonight is a typical video and dvd movie rental outlet for home-viewing customers. During the weeknig

pentagon [3]

Answer:

Probability [No customers in system] = 0.375
Customers waiting for service = 25/24
Average time customer wait = 1.25/1.5
May be wait
Per customer average time = 1.33 (Approx)

Step-by-step explanation:

Given:

Arrival rate λ = 1.25 min

Mean μ = 2

Computation:

(a) Probability [No customers in system]

Probability [No customers in system] = 1-[λ/μ]

Probability [No customers in system] = 1-[1.25/2]

Probability [No customers in system] = 0.375

(b) Customers waiting for service

Customers waiting for service = λ²/ [μ(μ-λ)]

Customers waiting for service = 1.25²/ [2(2-1.25)]

Customers waiting for service = 25/24

(c) Average time customer wait

Average time customer wait = λ / [μ(μ-λ)]

Average time customer wait = 1.25/ [2(2-1.25)]

Average time customer wait = 1.25/1.5

(d) May be wait because Customers waiting for service = 25/24

(e) Per customer average time

Per customer average time = 1/(μ-λ)

Per customer average time = 1/(2-1.25)

Per customer average time = 1.33 (Approx)

7 0

3 years ago

Factorise the following :

Free_Kalibri [48]

Answer:

(3x+4b)(a-2y)

Step-by-step explanation:

(3ax-6xy)+(8by-4ab)

3x(a-2y) -4b(-2y+a)

(3x+4b) (a-2y)

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3 years ago

Read 2 more answers

A science teacher has a supply of 5% hydrochloric acid and a supply of 65% hydrochloric acid(HC1). How much of each solution sho

Sphinxa [80]

Assume that the amount needed from the 5% solution is x and that the amount needed from the 65% solution is y.

We are given that, the final solution should be 42 ml, this means that:
x + y = 42 ...........> equation I
This can also be written as:
x = 42-y .......> equation II

We are also given that the final concentration should be 45%, this means that:
5% x + 65% y = 45% (x+y)
0.05x + 0.65y = 0.45(x+y)

We have x+y = 42 from equation I, therefore:
0.05x + 0.65y = 0.45(42)
0.05x + 0.65y = 18.9 .........> equation III

Substitute with equation II in equation III as follows:
0.05x + 0.65y = 18.9
0.05(42-y) + 0.65y = 18.9
2.1 - 0.05y + 0.65y = 18.9
0.6y = 18.9 - 2.1
0.6y = 16.8
y = 28 ml

Substitute with y in equation II to get x as follows:
x = 42-y
x = 42 - 28
x = 14 ml

Based on the above calculations:
amount of 5% solution = x = 14 ml
amount of 65% solution = y = 28 ml
The correct choice is:
The teacher will need 14 mL of the 5% solution and 28 mL of the 65% solution.

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4 years ago

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Answer:

13: 30

Step-by-step explanation:

All you have to do is make sure that you put the ice skating fist because that is the one that the question mentioned first. Hope this helps :)

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3 years ago