The discriminant of a polynomial is described as 0 = b^2 - 4ac (you may recognize that from the numerator of the quadratic formula; it's the part under the square root).
In this case, add 1 to both sides of the equation so you get 9x^2 + 6x + 1 = 0
Now it's in the proper form to use the discriminant.
Note that when solving, there are 3 possibilities; x can be >0, x can be <0, or x can be =0.
If
• x < 0, The equation has no real roots.
• x = 0, The equation has 1 real root
• x > 0, The equation has 2 real roots
b^2 - 4ac = x
6^2 - 4(9)(1) = x
36 - 36 = x
0 = x
Since x = 0, the equation of 9x^2 + 6x + 1 = 0 has 1 real root (one x-intercept).
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Verified answer
The discriminant of a polynomial is described as 0 = b^2 - 4ac (you may recognize that from the numerator of the quadratic formula; it's the part under the square root).
In this case, add 1 to both sides of the equation so you get 9x^2 + 6x + 1 = 0
Now it's in the proper form to use the discriminant.
Note that when solving, there are 3 possibilities; x can be >0, x can be <0, or x can be =0.
If
• x < 0, The equation has no real roots.
• x = 0, The equation has 1 real root
• x > 0, The equation has 2 real roots
b^2 - 4ac = x
6^2 - 4(9)(1) = x
36 - 36 = x
0 = x
Since x = 0, the equation of 9x^2 + 6x + 1 = 0 has 1 real root (one x-intercept).
Hope this helps!