Using vertex form, write the equation of the parabola with a vertex at (1,1)

and a y-intercept at (0,2)
.(1 point)
The equation in vertex form is
.

1 answer

To write the equation of a parabola in vertex form, we use the formula:

\[ y = a(x - h)^2 + k \]

where \((h, k)\) is the vertex of the parabola. In this case, the vertex is \((1, 1)\), so we have:

\[ y = a(x - 1)^2 + 1 \]

Next, we need to find the value of \(a\). We can use the given y-intercept \((0, 2)\). Plugging in these coordinates into the equation, we have \(x = 0\) and \(y = 2\):

\[ 2 = a(0 - 1)^2 + 1 \]

This simplifies to:

\[ 2 = a(1) + 1 \]

\[ 2 = a + 1 \]

Now, solve for \(a\):

\[ a = 2 - 1 \] \[ a = 1 \]

Therefore, we can substitute \(a\) back into the vertex form equation:

\[ y = 1(x - 1)^2 + 1 \]

This can be simplified to:

\[ y = (x - 1)^2 + 1 \]

Thus, the equation of the parabola in vertex form is:

\[ \boxed{y = (x - 1)^2 + 1} \]