Results 1 to 5 of 5

Math Help - the equation of a straight line

  1. October 13th 2008, 11:05 AM #1
    coyoteflare
    coyoteflare is offline
    Junior Member
    Joined
    Oct 2008
    Posts
    50

    the equation of a straight line

    the equation of stralight line is 3x+2y=11 find the equation of the parrallel line passing through the point 2,5

    i got y=2/3x +7 1/3

    or is it y=2/3x -4.5
    Follow Math Help Forum on Facebook and Google+
  2. October 13th 2008, 11:29 AM #2
    masters
    masters is offline
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    MHF Donor
    Quote Originally Posted by coyoteflare View Post
    the equation of stralight line is 3x+2y=11 find the equation of the parrallel line passing through the point 2,5

    i got y=2/3x +7 1/3

    or is it y=2/3x -4.5
    3x+2y=11

    2y=-3x+11

    y=-\frac{3}{2}x+\frac{11}{2}

    Slope(m) = -\frac{3}{2}

    Use slope-intercept form of the linear equation: y=mx+b and (2, 5) and solve for b.

    y=mx+b

    5=-\frac{3}{2}(2)+b

    5=-3+b

    8=b

    Substituting back into y=mx+b, we have:

    y=-\frac{3}{2}x+8
    Follow Math Help Forum on Facebook and Google+
  3. October 13th 2008, 11:29 AM #3
    earboth
    earboth is offline
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,829
    Thanks
    123
    Quote Originally Posted by coyoteflare View Post
    the equation of stralight line is 3x+2y=11 find the equation of the parrallel line passing through the point 2,5

    i got y=2/3x +7 1/3

    or is it y=2/3x -4.5
    The LHS of the equation of the parallel must be 3x + 2y too. To calculate the RHS you only have to plug in the coordinates of the given point. Thus the equation of the parallel is:

    \boxed{3x+2y=16}
    Follow Math Help Forum on Facebook and Google+
  4. October 13th 2008, 11:35 AM #4
    coyoteflare
    coyoteflare is offline
    Junior Member
    Joined
    Oct 2008
    Posts
    50

    i feel so stupid sorry i meant..

    Quote Originally Posted by masters View Post
    3x+2y=11

    2y=-3x+11

    y=-\frac{3}{2}x+\frac{11}{2}

    Slope(m) = -\frac{3}{2}

    Use slope-intercept form of the linear equation: y=mx+b and (2, 5) and solve for b.

    y=mx+b

    5=-\frac{3}{2}(2)+b

    5=-3+b

    8=b

    Substituting back into y=mx+b, we have:

    y=-\frac{3}{2}x+8
    ..perpendicular.. sorry not parrallel...

    getting confused cus im trying to do binomials too
    Follow Math Help Forum on Facebook and Google+
  5. October 13th 2008, 11:56 AM #5
    masters
    masters is offline
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    MHF Donor
    Quote Originally Posted by coyoteflare View Post
    ..perpendicular.. sorry not parrallel...

    getting confused cus im trying to do binomials too
    In that case, just change the slope to \frac{2}{3} which is the negative reciprocal of -\frac{3}{2} and then proceed the same way.

    5=\frac{2}{3}(2)+b

    5=\frac{4}{3}+b

    \frac{11}{3}=b

    The equation of the perpendicular is y=\frac{2}{3}x+\frac{11}{3}
    Follow Math Help Forum on Facebook and Google+
« the equation of a straight line is 3x+2y=11. find the equation of a parrallel line pa | graphing »

Similar Math Help Forum Discussions

  1. Equation of a straight line
    Posted in the Algebra Forum
    Replies: 6
    Last Post: June 30th 2011, 01:21 PM
  2. [SOLVED] Equation of straight line
    Posted in the Algebra Forum
    Replies: 4
    Last Post: June 17th 2011, 11:30 AM
  3. Equation of the straight line
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: March 26th 2010, 04:29 AM
  4. equation of a straight line.
    Posted in the Algebra Forum
    Replies: 1
    Last Post: February 13th 2009, 01:29 PM
  5. the equation of a straight line is 3x+2y=11. find the equation of a parrallel line pa
    Posted in the Pre-Calculus Forum
    Replies: 5
    Last Post: October 13th 2008, 10:16 AM

Search Tags


/mathhelpforum @mathhelpforum