I have two datasets, one being sparser than the other. They look like this:

Data Set 1:

 4   50
 5   55
 6   60
 7   70
 8   80

Data Set 2:

 4   10
 6   20
 8   30

I have several hundred points instead of this few. I want them in the same graph, the X axis being 4-8, the y axis being 0-100ish, and two lines, one for each data set.

What I get is two lines, not correlated at all along the X axis, and the X axis being labeled from one of the two datasets, with the labels being wrong for the other. The smaller data set is one-point-per-tick on the x axis, when I need it to skip ticks and actually line up with the other data set.

Not married to excel, willing to try this in something else if it's free.