(quiet, asians)
x-7 = 19+x
x^2 -7x = 19x + x^2
subtract 19x+x^2 from both sides
-7x - 19x = 0
x = 0 QED
Solve for x
(quiet, asians)
x-7 = 19+x
x^2 -7x = 19x + x^2
subtract 19x+x^2 from both sides
-7x - 19x = 0
x = 0 QED
Incorrect. If you substitute x = 0 then you will get -7 = 19 which is wrong. The correct answer is no solution.
Proof
<pre>
x-7 = 19 + x
-x -x</pre>
-7 = 19, a contradiction indicating no solution.
You can see the fallacy in your work because ito get x=0 you had to multiply everything by x. However assume x is 0 you are simply multiplying everything by zero and all information is lost.
but I added and mutiplied everything on both sides. Ergo it is valid. x = 0Originally Posted by qwertysaur
correct, x=nrn
This post brought to you by the power of boobs. Dear lord them boobs. Amen
This, you can see it without doing any work.
It's only valid if you plug it back in and get a valid result.
I thought I told you guys NO ASIANS
Apparently "asians" are anyone who knows anything about math.
Speaking of which, we haven't had a "does 0.999... = 1?" thread in a while.
Why would you want to do that again?
racist
This post brought to you by the power of boobs. Dear lord them boobs. Amen
Because the people who refuse to accept it are always entertaining. And math is fun.Why would you want to do that again?
Regardless I'm correct. x = 0 and 26 = 0 . But x != 26 that would be a fallacy.Because the people who refuse to accept it are always entertaining. And math is fun.Why would you want to do that again?
If you want to prove that x = 0, then you can't multiply both sides of the equation by x to get that solution, because it will always result in 0 = 0. (Side note you also can't divide by x to prove x = 0 because dividing by zero results in no solution.) Take for example x+1 = 2. It should be obvious that x = 1, but lets go with pg's method. Multiply everything by x to get x<sup>2</sup>+x = 2x. Subtract 2x from both sides and you get x<sup>2</sup>-x = 0. Factor and you have (x)(x-1) = 0, giving the solutions x=0 and x=1. However, if x=0 then you get 1 = 2 which is a contradiction.but I added and mutiplied everything on both sides. Ergo it is valid. x = 0
There are many problems where you have to reject a solution because an answer makes no sense. For example you have a rectangle where the length of one side is three units less than that of the other, and the area is found to be 4 square units. You get (x)(x-3) = 4, which becomes x<sup>2</sup>-3x = 4. Subtract 4 form both sides to get x<sup>2</sup>-3x-4 = 0. Factor to get (x-4)(x+1) = 0. So x = 4 or x = -1. You have to reject x = -1 because you can't have a side with negative length.
Remember to always check to make sure your solutions actually make sense. Also when using an esoteric process for finding the solution, make sure there is no way that is easier first. Don't use calculus to find the area of a circle, just use A = πr<sup>2</sup>. The calculus method is possible, but much more time consuming.
oh EoFFIf you want to prove that x = 0, then you can't multiply both sides of the equation by x to get that solution, because it will always result in 0 = 0. (Side note you also can't divide by x to prove x = 0 because dividing by zero results in no solution.) Take for example x+1 = 2. It should be obvious that x = 1, but lets go with pg's method. Multiply everything by x to get x<sup>2</sup>+x = 2x. Subtract 2x from both sides and you get x<sup>2</sup>-x = 0. Factor and you have (x)(x-1) = 0, giving the solutions x=0 and x=1. However, if x=0 then you get 1 = 2 which is a contradiction.but I added and mutiplied everything on both sides. Ergo it is valid. x = 0
There are many problems where you have to reject a solution because an answer makes no sense. For example you have a rectangle where the length of one side is three units less than that of the other, and the area is found to be 4 square units. You get (x)(x-3) = 4, which becomes x<sup>2</sup>-3x = 4. Subtract 4 form both sides to get x<sup>2</sup>-3x-4 = 0. Factor to get (x-4)(x+1) = 0. So x = 4 or x = -1. You have to reject x = -1 because you can't have a side with negative length.
Remember to always check to make sure your solutions actually make sense. Also when using an esoteric process for finding the solution, make sure there is no way that is easier first. Don't use calculus to find the area of a circle, just use A = πr<sup>2</sup>. The calculus method is possible, but much more time consuming.
ps aren't you aznnnn?
math is for losers.
and bert. asl?
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