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A) y = 2 - 6x
B) 1/2y - x = 1
A) 6x + y =2
Multiply B) by -2
B) -y + 2x = -2 then add it to A)
8x = 0
x = 0
y = 2
Answer is A
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Let x represent the amount of 10% solution used.
Let y represent the amount of 25% solution used.
Since 30 liters of 15% solution are being made, our first equation is
x + y = 30
Now we deal with the actual peroxide in each solution.
x liters of 10% peroxide contain 0.1x liters of peroxide.
y liters of 25% peroxide contain 0.25y liters of peroxide.
30 liters of 15% peroxide contain 0.15 * 30 = 4.5 liters of peroxide.
From this information, we can write our second equation.
0.1x + 0.25y = 4.5
We have a system of equations:
x + y = 30
0.1x + 0.25y = 4.5
Multiply the first equation by -0.25 and add to the second equation.
-0.25x - 0.25y = -7.5
0.1x + 0.25y = 4.5
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-0.15x = -3
x = 20
Answer: 20 liters
Answer:
x= -10
Step-by-step explanation:.......
Consider the following definitions for sets of characters: Digits = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} Letters = {a, b, c, d, e, f,
kirill [66]
Answer:
There are 14 choices for the first character because there are 4 + 10 digits and special characters. There are 40 choices for each of the remaining characters. Putting the choices together by the product rule, the total number of strings of length j in which the first character is not a letter is 14·40^(j-1)
14·40^6 + 14·40^7 + 14·40^8 = 14(40^6 + 40^7 + 40^8)
IDK
