SOLUTION: How many real number solutions does the quadratic equation 2x^2+7x-9 have?

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Question 967295: How many real number solutions does the quadratic equation 2x^2+7x-9 have?
Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!

Calculate the discriminant of the quadratic equation

2x%5E2%2B7x-9 = 0.

It is  d = b%5E2+-4ac = 7%5E2+-+4%2A2%2A%28-9%29 = 49+%2B+4%2A2%2A9 = . . .

You even do not need to calculate the exact value to answer the question:  it is clear that the discriminant is a positive number.

Hence,  the given quadratic equation has two real roots.