Set up a system of equations:
x + y = 9
1/x +1/y = 1/2
The easiest way to solve would be substitution.
x + y = 9 can be solved for y:
y = 9 - x
Then plug this into the second equation and solve for x:
1/x + 1/(9-x) = 1/2
(9-x) + x = x(9-x)/2
9 = (9x-x²)2
18 = 9x - x²
x² - 9x + 18 = 0
(x-6)(x-3) = 0
x = 6, 3
You can check your answer by plugging the two numbers back into both of the equations:
6 + 3 = 9
1/6 + 1/3 = 1/2
The two numbers are 6 and 3.
<span> x^2 +(x-4)^2 =20^2</span>
<span> x^2 +(x-4)^2 =400</span>
x^2 +(x-4)^2 -400=0
factor:
2x^2-8x-384=0
Factor the 2 out of 2X^2
2(x-16) (x+12) =0
<span> Divide both sides by 2</span>
(x-16) (x+12) =0
X=16 , x=-12
<span> Number cannot be negative so x=16</span>
4 Dollars - 100%
3.60 Dollars - ?
Just Cross Multiply
4X = 360
X = 360/4
X = 90%
100%-90% = 10℅
The percent change is 10 percent
The answer is: "10 cm" .
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Method 1)
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2L + 2w = 40 ; Since the formula for perimeter of a rectangle (Note: a square is a rectangle) is:
P = 2L + 2w ; Note: L = length; w = width; P = perimeter;
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Factor out a "2":
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" 2L + 2w = 40" ;
2 (L+ w) = 40;
Divide each side of the question by "2" ;
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[2 (L + w)] / 2 = 40 / 2 ;
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to get: (L + w) = 20 ;
Note: this "rectangle is a square" ; so L= w".
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20 /2 = 10 ;
L + w = 10 + 10 = 20.
This is a square, so each side of the square is the same length.
Each side is: 10 cm .
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Method 2)
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We are given: The perimeter (sum of the lengths of all sides) of a square is "40 cm." Since a square has 4 sides of equal length:
Each side is: 40 cm / 4 = 10 cm.
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Answer:
6x^2^x^2+x^4
Step-by-step explanation:
