the midpoint formula is x1 + x2 divided by 2, y1 + y2 divided by two.

if the coordinates are x1: a, y1:b and x2: c, y2: 0, what is the midpoint?
I have found the y coordinate of the midpoint to be b over 2. I found the x to be a-c over two. Is this correct? Can it be simplified more than that?

Why is xmid=(a-c)/2 ? why not (a+c)/2 ?

Ooops, that was a typo. It should be "+". Now, is that completely simplified?

yes.

thanks

Yes, your calculations for the y-coordinate of the midpoint (b/2) and the x-coordinate of the midpoint ((a-c)/2) are correct based on the midpoint formula. However, it is not possible to simplify the expression for the x-coordinate any further.

The midpoint formula you mentioned is indeed correct: the x-coordinate of the midpoint is given by (x1 + x2)/2, and the y-coordinate of the midpoint is given by (y1 + y2)/2.

In this case, with x1 = a, y1 = b, x2 = c, and y2 = 0, we can substitute these values into the formula to find the midpoint coordinates:

x-coordinate of midpoint = (a + c)/2
y-coordinate of midpoint = (b + 0)/2 = b/2

So the coordinates of the midpoint are ((a + c)/2, b/2), which matches your calculations.