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Art [367]
3 years ago
15

X and y is the variable 4x-7y=3 x-7y=-15 what is the answer please

Mathematics
1 answer:
andrezito [222]3 years ago
6 0
Use linear combination to solve this. It is much faster than substitution. I would start by multiplying the bottom equation by -1.
<span>4x-7y=3
-x+7y=15</span>
Then, add the two equations together. The result is:
3x=18.
You've eliminated one variable. Now you can solve for the other one.
Divide both sides by 3 to get
x=6
Plug this into one of the original equations, then solve for y
-(6)+7y=15
7y=21
y=3

Check your work by plugging these values into both equations to see if they remain true

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Mr. Arju wishs to purchase a house . to buy the house he needs to make a down payment of nu.300000 and also pay nu.15000 every q
mojhsa [17]

Answer:

The price of the house is $ 853,735.05.

Step-by-step explanation:

Since Mr. Arju wishes to purchase a house, and to buy the house he needs to make a down payment of $ 300,000 and also pay $ 15,000 every quarter for the next 8 years, if the interest charge is 9% per year compounded quarterly, to determine what is the price of the house, the following calculation must be performed:

300,000 + (15,000 x 12 x 8) = X

300,000 + (180,000 x 8) = X

300,000 + 1,440,000 = X

1,740,000 = X

X x (1 + 0.09 / 4) ^ 8x4 = 1,740,000

X x (1 + 0.0225) ^ 32 = 1,740,000

X x 1.0225 ^ 32 = 1,740,000

X x 2.0381030257737 = 1,740,000

X = 1,740,000 / 2.03810

X = 853,735.05

Therefore, the price of the house is $ 853,735.05.

5 0
3 years ago
Factor: 100x^2- 81
Alex17521 [72]

Answer:

Choice 'D' (10x + 9) (10x-9) is the correct answer

Step-by-step explanation:

100x^2 - 81

This is a difference of squares...

therefore = (10x + 9) (10x - 9)

7 0
3 years ago
Find all the perfect cubes between 1000 and 2000.
Nadya [2.5K]
There are only 2 perfect cubes in between 1000 and 2000.

11^3 = 1331
12^3 = 1728
8 0
3 years ago
What is the correct inverse function for f(x) = e2x ?
Lena [83]
To solve this problem you must appy the proccedure shown below:

 1. You have the following function given in the problem above:

 f(x)=e^2x

 2. You can rewrite is:

 y=e^2x

 3. Interchange the variables, as below:

 x=e^2y

 3. The inverse of an exponential function is the logarithm function. Thereforem you have:

 ln(x)=ln(e^2y)
 ln(x)=2y

 4.Then, you have:

 y=ln(x)/2

 Therefore, the answer is: 

 f^-1(x)=ln(x)/2
 
5 0
3 years ago
Which of the equations is the correct representation of the following word problem
stiks02 [169]

Answer: (80+90+z)/3=90

Step-by-step explanation:

3 0
3 years ago
Read 2 more answers
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