Part A)The given equation is:

The radicand or discriminant(d) of the equation will be:

Since the discriminant is equal to 0, the given quadratic equation has only 1 root. In other words we can say the the given equation is a perfect square.
Part B)The given equation is:

We can solve this expression by factorization. Factors of middle term are to be made in such a way that their product equals the product of first and third term and sum is equal to the middle term i.e. product should be 4x² and sum should be -4x.
So the two such terms are -2x and -2x. Using the factors and simplifying the equation by taking common we get:
Answer:
x=-3
Step-by-step explanation:
There can be more then 1 mode.
Sometimes, there is not even a mode.....and other times, there is 1 mode.
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