Question
Question: How do you state the coordinates of the vertex of the parabola whose equation is : \(y = 3{\left( {x...
How do you state the coordinates of the vertex of the parabola whose equation is : y=3(x−2)2+5?
Solution
This problem deals with the conic sections. A conic section is a curve obtained as the intersection of the surface of a cone with a plane. There are three such types of conic sections which are, the parabola, the hyperbola and the ellipse. This problem is regarding one of those conic sections, which is a parabola. The general form of an equation of a parabola is given by x2=4ay.
Complete step-by-step answer:
Now consider the given parabola equation y=3(x−2)2+5.
Simplifying the given parabola equation as given below:
⇒y=3x2−12x+17
If the parabola is given by y=ax2+bx+c, then the x-coordinate of the vertex is given by:
⇒x=2a−b
Here in the given parabola equation y=3x2−12x+17, here a=3,b=−12 and c=17.
Now finding the x-coordinate of the vertex:
⇒x=2(3)−(−12)
⇒x=2
Now to get the y-coordinate of the vertex of the parabola, substitute the value of x=2, in the parabola equation, as shown below:
⇒y=3(2)2−12(2)+17
⇒y=3(4)−24+17
Simplifying the above equation, as given below:
⇒y=12−7
∴y=5
So the vertex of the parabola y=3x2−12x+17 is A, which is given by:
⇒A=(2,5)
This parabola has its axis parallel to y-axis.
The graph of the given parabola is shown below:
Final answer: The vertex of the parabola is (2,5).
Note:
Please note that if the given parabola isx2=4ay, then the vertex of this parabola is the origin (0,0), and there is no intercept for this parabola as there are no terms of x or y. If the equation of the parabola includes any terms of linear x or y, then the vertex of the parabola is not the origin, the vertex has to be found by simplifying it into its particular standard form.