Why is the solution to ax+b=c unique?

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brad sue
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Hi,
Please can someone help me with this problem.

show that a,b,c are real numbers and a#0, then there is a unique solution of the equation ax+b=c.

the uniqueness of the solution is my problem.
Thank you
B
 
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If the uniqueness is the problem, then suppose there were two solutions, x1 and x2. Since they are solutions to that equation, you must have, of course, ax1+ b= c and ax2+ b= c. Subtracting one equation from the other, a(x1- x2)= 0. What does that tell you?
 
HallsofIvy said:
If the uniqueness is the problem, then suppose there were two solutions, x1 and x2. Since they are solutions to that equation, you must have, of course, ax1+ b= c and ax2+ b= c. Subtracting one equation from the other, a(x1- x2)= 0. What does that tell you?


That's right. we can ay that x1=x2. so unique soltuion
thanks