SOLUTION: totally lost quadratic equation ax^2+bx+c=0 solution 8, only solution The equation is _____=0

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Question 131760: totally lost
quadratic equation
ax^2+bx+c=0
solution 8, only solution
The equation is _____=0

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Write the quadratic equations (ax%5E2%2Bbx%2Bc+=+0) given the solution is x = 8.
Now, quadradic equation have two solutions, so when you say that x = 8 is the only solution, this means the equation has a "double solution" of x = 8 and x = 8.
So, we work backwards from the solutions to the equation as follows:
Start with the solutions:
x+=+8 and x+=+8 This means that the parabola generated by the equation touches the x-axis at the point x = 8,
In solving the equation, there had to be two factors that were equal to zero and these factors are:
x-8+=+0 and x-8+=+0 so if we now multiply these factors together, we will arrive at the original equation.
%28x-8%29%28x-8%29+=+x%5E2-16x%2B64+=+0 This is the equation.
Check:
We know that if the discriminant (b%5E2-4ac) of a quadratic equation is equal to zero, then the equation has a double root.
In this case, the equation we just generated shows us that a = 1, b = 16, and c = 64. Let's see if the discriminant does equal zero.
b%5E2-4ac+=+16%5E2-4%281%29%2864%29 = 256-256+=+0