2. Add \a and 1/3. Use 12 as the common denominator

Step-by-step explanation:

Since I have to assume a is part of the fraction. We will answer assuming /a is replaced with a/12 + 1/3

To write 12/a as a fraction we must multiply with a common denominator. Thus being 3/3.

Now to write 1/3 as a fraction with a common denom we must use a/a.

Then we want to write each expression with a common denominator of a * 3 and multiply by a factor of 1.

Then we want to multiply 1/3 and a/a.

Then we reorder the factors of a *3.

Next, we combine the numerators over the common denom.

FInally, we multiply 12 by 3.

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this