Question

The vertex of this parabola is at (3, 5) . When the y-value is 6, the x-value is - 1 What is the coefficient of the squared term in the parabola's equation? (3, 5) A. -4 B. 4 C. 2 D.2

Answer 1

The correct approach is Option A (-4).

Explanation:

The given values are:

Vertex of the parabola,

(h, k) = (3, 5)

Passing through,

(x, y) = (-1, 6)

As we know,

The equation of parabola is:

⇒
`x=a(y-k)^2+h`

On substituting the given values in the above equation, we get

⇒
`-1=a(6-5)^2+3`

⇒
`-1=a+3`

On substracting "3" from both sides, we get

⇒
`-1-3=a+3-3`

⇒
`a=-4` (coefficient of squared term)

Thus the above is the right choice.