Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 155043: I'm not sure how to do this, and i need some help.
consider the equation x^2+2x=7. Prove that this equation has two real roots.: I'm not sure how to do this, and i need some help.
consider the equation x^2+2x=7. Prove that this equation has two real roots.
Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+2x=7 Start with the given equation


x^2+2x-7=0 Subtract 7 from both sides


Solved by pluggable solver: Computing the Discriminant


From x^2+2x-7 we can see that a=1, b=2, and c=-7



D=b^2-4ac Start with the discriminant formula.



D=(2)^2-4(1)(-7) Plug in a=1, b=2, and c=-7



D=4-4(1)(-7) Square 2 to get 4



D=4--28 Multiply 4(1)(-7) to get (4)(-7)=-28



D=4+28 Rewrite D=4--28 as D=4+28



D=32 Add 4 to 28 to get 32



Since the discriminant is greater than zero, this means that there are two real solutions.