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A quadratic equation is shown below: 25x2 + 10x + 1 = 0 Part A: Describe the solution(s) to the equation by just determining the radicand. Show your work. (5 points) Part B: Solve 4x2 − 4x + 1 = 0 by using an appropriate method. Show the steps of your work, and explain why you chose the method used. (5 points)

User Malganis
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a) The quadratic equation is:

25x^2 + 10 x +1 =0
which is of the form

ax^2 + bx+c=0
Let's analyze the radicand:

b^2-4ac=(10)^2 - 4\cdot 25 \cdot 1=100-100 =0
The radicand is zero: this means that the equation has 2 coincident solutions.

We can find them by using the formula:

x= (-b \pm √(b^2-4ac) )/(2a)= (-10 \pm 0)/(2 \cdot 25)=-0.2
So, the solution is x=-0.2 with multiplicity 2.

b) The equation is

4x^2-4x+1=0
Note that the radicand is zero again, as before:

b^2-4ac=4^2 - 4\cdot 4 \cdot 1=16-16=0
So we have two coincident solutions as before. We can find them using the same formula:

x= (-b \pm √(b^2-4ac) )/(2a)= (-(-4) \pm 0 )/(2 \cdot 4)= (4)/(8)=0.5
So, the solution is x=0.5 with multiplicity 2.
User Abasterfield
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