SOLUTION: what does it mean when they say what is the discriminate for the problem 7x^2-8x+5=0 I am totally totally lost.

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Question 325815: what does it mean when they say what is the discriminate for the problem 7x^2-8x+5=0 I am totally totally lost.
Found 2 solutions by unlockmath, solver91311:
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
(Hint: the key to Algebra is understanding the words and symbols. Once you conquer that the subject is a breeze)
Discriminate is as follows:
In the quadratic formula below b^2-4ac is the discriminate.
x = (-b +- sqrt( b^2-4*a*c ))/(2*a)
So in this equation:
7x^2-8x+5=0
the discriminate is
8^2-4*7*5 or
-76
Make sense?
RJ

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


For any quadratic polynomial equation of the form:



Find the Discriminant, and evaluate the nature of the roots as follows:


Two real and unequal roots. If is a perfect square, the quadratic factors over .

One real root with a multiplicity of two. That is to say that the trinomial is a perfect square and has two identical factors.

A conjugate pair of complex roots of the form where is the imaginary number defined by

For your problem:



Hence, , , and

So

Therefore, you have a conjugate pair of complex roots.

John