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3 years ago

2x - y - 4 = 0

Mathematics

2 answers:

natka813 [3]3 years ago

7 0

2x-y=4
3x+y=9

5x=13

x=13/5

3(13/5)+y=9

39/5+y=45/5

y=45/5-39/5

y=6/5

the answer is b

Aleks [24]3 years ago

6 0

So to start you should get x and y on the same side and get the numbers on one side. Then you should cancel out a variable. Because both y’s are 1 and they are opposite charges they will both cancel out to 0. Then add what is remaining which is the 2x and the 3x and equal that to +9-4 which equals 5. You want x to be all by itself so you would divide both sides by 5 and get that x=1. Then you would just substitue and solve for y. Hope this helped!

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Answer:

B) Cube

Step-by-step explanation:

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3 years ago

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Firdavs [7]

Answer:

Emma spend 8 hours in homework in a week and Jared spends 16 hours in homework in 2 weeks.

Step-by-step explanation:

Two quantities P and Q are said to be in PROPORTION if and only if for all values of P and q, we get:

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Here, k : PROPORTIONALITY CONSTANT

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Case 2:

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Case: 3

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Case: 4

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Case: 5

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6 0

3 years ago

Read 2 more answers

Kristen invests $ 5745 in a bank. The bank 6.5% interest compounded monthly. How long must she leave the money in the bank for i

podryga [215]

Answer:

1. 10.7 years

2. 17.0 years

3. 2nd option

Step-by-step explanation:

Use formula for compounded interest

$A=P\cdot \left(1+\dfrac{r}{n}\right)^{nt},$

where

A is final value, P is initial value, r is interest rate (as decimal), n is number of periods and t is number of years.

In your case,

1. P=$5745, A=2P=$11490, n=12 (compounded monthly), r=0.065 (6.5%) and t is unknown. Then

$11490=5745\cdot \left(1+\dfrac{0.065}{12}\right)^{12t},\\ \\2=(1.0054)^{12t},\\ \\12t=\log_{1.0054}2,\\ \\t=\dfrac{1}{12}\log_ {1.0054}2\approx 10.7\ years.$