- #1
Tony Zalles
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Problem: 1 - x-3/x-2 = 2x-3/x-2
OK I know the answer in the back of our textbook is: No Solution
Yet...
I work out the problem to get, x=2
Here is how I got that.
Now I know that if 2 is put back in for x undefined values occur.
1 - (undefined value) = (undefined value)
So what I don't understand is how is x=2 a solution if it doesn't work in the original equation?
And if it is not an actual solution than how come it came up as one?
2nd Problem:
[Earth Science]
In 1984, the Soviets led the world in drilling the deepest hole in the Earth's crust--more than 12 kilometers deep. They found that below 3 kilometers the temperature T increased 2.5 (degrees) C for each additional 100 meters of depth.
(A) If the temperature at 3 kilometers is 30 (degrees) C and x is the depth of the hole in kilometers, write an equation using x that will give the temperature T in the hole at any distance beyond 3 kilometers.
Ok I figured that: T = 2.5[(x-3)/100] + 30
But the answer is different...
[Answer: T = 30 + 25(x-3)]
But...if you put in a number, x in meters, in my equation, and put in a number x in km, in the 'back of the books equation' you get the same answer.
T(4000 m) = 55 (degrees) C
T(4 km) = 55 (degrees) C
So...not sure which is 'right' per say, some help would be nice...
Thanks.
-Tony Zalles
OK I know the answer in the back of our textbook is: No Solution
Yet...
I work out the problem to get, x=2
Here is how I got that.
[x-2) - (x-3)]/x-2 = 2x-3/x-2
x-2-x+3=2x-3
4=2x
2=x
x-2-x+3=2x-3
4=2x
2=x
Now I know that if 2 is put back in for x undefined values occur.
1 - (undefined value) = (undefined value)
So what I don't understand is how is x=2 a solution if it doesn't work in the original equation?
And if it is not an actual solution than how come it came up as one?
2nd Problem:
[Earth Science]
In 1984, the Soviets led the world in drilling the deepest hole in the Earth's crust--more than 12 kilometers deep. They found that below 3 kilometers the temperature T increased 2.5 (degrees) C for each additional 100 meters of depth.
(A) If the temperature at 3 kilometers is 30 (degrees) C and x is the depth of the hole in kilometers, write an equation using x that will give the temperature T in the hole at any distance beyond 3 kilometers.
Ok I figured that: T = 2.5[(x-3)/100] + 30
But the answer is different...
[Answer: T = 30 + 25(x-3)]
But...if you put in a number, x in meters, in my equation, and put in a number x in km, in the 'back of the books equation' you get the same answer.
T(4000 m) = 55 (degrees) C
T(4 km) = 55 (degrees) C
So...not sure which is 'right' per say, some help would be nice...
Thanks.
-Tony Zalles
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