What are the coordinated of the point 3?4 of the way from A(-6,-3) to B (10,9)

Answer 1

If the co-ordinates of A are (a,c) and of B are (b,d), then the co-ordinates of a point 100p% of the way from A to B are [(1-p)a + pc,(1-p)b + pd].

In your problem p=.75.

Note: this is a consequence of the so-called Side Splitter Theorem from plane geometry.