Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

ALGEBRA HELP pleasee (:?

the question is

there are two ordered pairs

(5,r) (r,6)

& the slope of the line has to be 5/8

what is r ?

& r has to be the same numberrr.

2 Answers

Relevance
  • ?
    Lv 7
    1 decade ago
    Favorite Answer

    Your last sentence carries no meaning. However if your question requires " finding out the value of ' r ' when the slope of the line = 5/8, Then, here is the solution -

    The slope of the line m = ( y2 - y1 ) / ( x2 - x1 ). In our case --

    y1 = r, y2 = 6, , x1 = 5, and x2 = r,

    Substituting these values in the above mentioned formula we get ----

    5/8 = ( 6 - r ) divided by ( r - 5 )

    => ( 6 - r ).8 = ( r - 5 ) .5

    => 48 - 8.r = 5.r - 25

    => 48 + 25 = 5.r + 8.r

    => 13.r = 73

    => r = 73/13 = 5 . 6 1 5 ........... Answer Answer

    ...............................................................................................

    CHECK

    Substitute r = 73/13 in eqn (1) –

    => ( 6 – r ) / ( r – 5 ) = ( 6 - 73/13 ) / (73/13 - 5 )

    = [ (78-73)/13 ] divided by [ (73 – 65) / 13 ]

    = ( 5/13 ) / (8/13)

    = 5/8 …………………. Which is the slope (given value)

    Hence value of r = 73/13 is correct .

  • Bob B
    Lv 7
    1 decade ago

    For the slope to be 5/8, (6 - r) / (r - 5) must equal 5/8 (the rise over the run is 5/8).

    (6 - r) / (r - 5) = 5/8

    Cross-multiply:

    5(r - 5) = 8(6 - r)

    Multiply it out:

    5r - 25 = 48 - 8r

    Add 8r to both sides:

    5r - 25 + 8r = 48 - 8r + 8r

    or

    13r - 25 = 48

    Add 25 to both sides:

    13r = 73

    Divide both sides by 13:

    r = 73/13

    The points will be (5, 73/13) and (73/13, 6)

    Check:

    Rise: 6 - 73/13 or 78/13 - 73/13 = 5/13

    Run: 73/13 - 5 or 73/13 - 65/13 = 8/13

    Slope: (5/13) / (8/13)

    Invert and multiply:

    (5/13) * (13/8) = 5/8

Still have questions? Get your answers by asking now.