To find the equation of the parabola in vertex form, we start with the vertex form equation of a parabola, which is given by:
\[ f(x) = a(x - h)^2 + k \]
where \((h, k)\) is the vertex of the parabola. From the information given, the vertex \((h, k)\) is \((6, 5)\). Thus, our equation becomes:
\[ f(x) = a(x - 6)^2 + 5 \]
Next, we need to determine the value of \(a\). We can do this by using the second point given, which is \((8, -3)\). We will substitute \(x = 8\) and \(f(x) = -3\) into the equation to solve for \(a\):
\[ -3 = a(8 - 6)^2 + 5 \]
This simplifies to:
\[ -3 = a(2)^2 + 5 \] \[ -3 = 4a + 5 \]
Next, we isolate \(a\) by subtracting 5 from both sides:
\[ -3 - 5 = 4a \] \[ -8 = 4a \]
Now, divide both sides by 4:
\[ a = -2 \]
Now that we have \(a\), we can substitute it back into the vertex form equation:
\[ f(x) = -2(x - 6)^2 + 5 \]
Therefore, the equation of the parabola in vertex form is:
\[ f(x) = -2(x - 6)^2 + 5 \]