The diameter of the circle is equal to the circumference divided by Pi.
Answer:
x = (c+a)/2
y = (c-a)/2
Step-by-step explanation:
Add the two equations and you get ...
(x +y) +(x -y) = (c) +(a)
2x = c+a
x = (c+a)/2
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Subtract the second equation from the first and you get ...
(x +y) -(x -y) = (c) -(a)
2y = c-a
y = (c-a)/2
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Comment on this problem
This is what I call a "sum and difference" problem. The solution shown here is (obviously) the generic solution to such a problem. Remembering this can get you quickly to the answer any time you're given the sum of two unknowns and their difference.
Answer:
The number that is represented by point E is -0.25
Step-by-step explanation:
Point E is between -1 and 0, -0.25 is also between -1 and 0, so the number that is most likely to be represented by point E is -0.25.
Y *x =20
y +x =9
rewrite 1st eq. as y = 20/x
subsituute that into 2nd eq.
20/x +x =9
multiply each term by X
20 +x^2 = 9x
subtract 9x from each side:
x^2 - 9x +20 = 0
now factor:
(x-5) (x-4) = 0
solve for x
5-5 = 0
4-4 = 0
so X can be 4 or 5
replace x into equations and solve for Y
so when X = 4, Y = 5
When X = 5, Y = 4
x= 5,4
y = 4,5
5, 3, -3, -7, -9
This is in descending order.
