Which of the following is a root of the polynomial?

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Roza

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Hello, I'm studying math for an ACT. I'm from Poland, so I had a different math school programme and I have a problem with this question. Which of the following is a root of the polynomial 2x2 – 6x + 3? I know the answer is: 3+ 3/2 but I have no clue how to solve it for this answer. It would be very nice if someone could explain it to me :) Thank you!
 
Roza said:
Hello, I'm studying math for an ACT. I'm from Poland, so I had a different math school programme and I have a problem with this question. Which of the following is a root of the polynomial 2x2 – 6x + 3? I know the answer is: 3+ 3/2 but I have no clue how to solve it for this answer. It would be very nice if someone could explain it to me :) Thank you!
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Do you know the definition of root of a real polynomial?

The real roots of a polynomial with real-coefficients are same as the x-intercepts of the graph of the polynomial.
 
Roza said:
Hello, I'm studying math for an ACT. I'm from Poland, so I had a different math school programme and I have a problem with this question. Which of the following is a root of the polynomial 2x2 – 6x + 3? I know the answer is: 3+ 3/2 but I have no clue how to solve it for this answer. It would be very nice if someone could explain it to me :) Thank you!
Click to expand...


just find all the values of x that will make the polynomial zero. In this case, it is best to use the quadratic formula.. http://www.purplemath.com/modules/quadform.htm

please take note that you can only use the quadratic formula when the form is of ax2 + bx + 3
 
Roza said:
...I have a problem with this question.

Q. Which of the following is a root of the polynomial 2x2 – 6x + 3?

I know the answer is: 3+ 3/2 but I have no clue how to solve it for this answer.
Click to expand...
"Roots" are "solutions" are "x-intercepts" (assuming you're working just in the real numbers).

The "x-intercepts" are where the associated graph, y = 2x^2 - 6x + 3, crosses (or touches; either way, the graph intercepts) the x-axis, which is also the line y = 0.

The "solutions" are the solutions to the related equation, 2x^2 - 6x + 3 = 0. This can be solved using the Quadratic Formula, for instance (here).

The "roots" are another name for the "solutions".

Hope that helps! ;)
 
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