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3 votes

{x}^(2) + 5x - 9 = 0

User Wsware
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1 Answer

6 votes
Pls be sure to include the instructions when you post a question. Are you to find the roots? y-intercept? axis of symmetry? ??

Let's solve for x (that is, let's find the roots):

x^2 + 5x - 9 = 0 => a=1, b=5, c= -9

-5 plus or minus sqrt(5^2 - 4(1)(-9)
Then, x = ----------------------------------------------------
2
-5 plus or minus sqrt(25+36)
x = -------------------------------------------
2
-5 plus or minus sqrt(51)
= ------------------------------------
2

Here we see that there are 2 real, unequal roots, both involving the square root of 51, which is not a perfect square.
-(5)
The equation of the axis of symmetry is x = --------- = -5/2
2

User Bienvenido David
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7.9k points