X = amount of the 60% solution
y = amount of the 75% solution
now, how much is 60% of x? well, (60/100) * x, or 0.6x.
and how much is 75% of y? well, (75/100) * y, or 0.75y.
well, the resulting mixture is 72% of acid and then water or other liquids, but we know is that much off 20 liters, how much is that then? well 72% of 20 is (72/100) * 20, or 14.4.
regardless of what "x" and "y" are, we know that the resulting substance has to be 20 liters, thus x + y = 20.
and we also know that the amount of acid in each amount, will add up to the acid in the resulting amount.
since we know that there is 0.6x liters of only acid and 0.75y liters of only acid in each, thus 0.6x + 0.75y = 14.4.
how many liters of "y"? well, y = 20 - x.
Answer:
(x, y) = (6, 2)
Step-by-step explanation:
You solve for x and y by writing equations that reflect the relation applicable to the given geometry.
The diagonals of a parallelogram bisect each other. That means the halves of each diagonal are equal.
2x -4 = 4y . . . . . . down diagonal
x +4 = 7y -4 . . . . . up diagonal
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We can subtract the first equation from 2 times the second equation to eliminate the x-variable.
2(x +4) -(2x -4) = 2(7y -4) -(4y)
2x +8 -2x +4 = 14y -8 -4y . . . . . . eliminate parentheses
12 = 10y -8 . . . . . . . . . . . . . . . . . collect terms
20 = 10y . . . . . . . . . . . . . . . . . . add 8
2 = y . . . . . . . . . . . . . . . . . . . . divide by 10
Substituting into the second equation gives ...
x +4 = 7(2) -4
x = 6 . . . . . . . . . . . . subtract 4
The values of x and y are (x, y) = (6, 2).
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The lengths of the diagonals are 20 and 16.
The formula for a parallelogram is
A=base*height or A=bh
A=38*35
A=1,330 sq in
Answer: Length = 24; width =4
Step-by-step explanation
Since the ratio of the length to width is 6:1
Let the length be represented as 6x
And the width be = x
Such that that the Perimeter of the rectangle which is
Perimeter = 2(length + width) becomes
56 = 2(6x + x)
56/2 = 6x+x
28 = 7x
x = 4
Width = 4
Length = 6x= 6 x 4 = 24
Answer:8
Step-by-step explanation: