Mathematics

Question

Segment addition postulate. Trying to help my son figure out how to solve. Given AC=39. A=2x-8, B=x×17. Find X, AB AND BC. We got 25 for X, and 42 for both AB, BC. Its not correct. 42+42 does not equal 39.

1 Answer

  • segment addition postulate says
    AB+BC=AC

    assuming that A, B, C are in order, and assuming that those are the points,

    legnth of AC=|A-C|=39 (|x| means absolute value of x)

    A=2x-8
    b=17x
    AB=|A-B|=|2x-8-17x|=|-8-15x|


    we are only given AB but not BC so this is not solvable unless you know BC
    AB+BC=AC
    BC=AC-AB

    BC=39-|-8-15x|
    that's as far as I can go since we don't know any more