Results 1 to 6 of 6

Math Help - Linear equations question grade 10

  1. #1
    Newbie
    Joined
    Oct 2012
    From
    Canada
    Posts
    15

    Post Linear equations question grade 10

    Need help with this one, would be appreciated if you could tell me how to solve this question.

    Dahlia walks from her house to school at 2km/h. After school she jogs back home at 6km/h and saves 15mins. how far does Dahlia live from school?

    Thanks!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Feb 2013
    From
    Saudi Arabia
    Posts
    443
    Thanks
    86

    Re: Linear equations question grade 10

    solve the equation 2x = 6(x-1/4) for x and find the time in hours .
    then multiply 2x to find the distance in KM ... as simple as such
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor

    Joined
    Apr 2005
    Posts
    16,421
    Thanks
    1856

    Re: Linear equations question grade 10

    Quote Originally Posted by xXplosionZz View Post
    Need help with this one, would be appreciated if you could tell me how to solve this question.
    Let t be the time it takes Dahlia to walk to school at 2 km/h in hours, x the distance she lives from school in km.

    Dahlia walks from her house to school at 2km/h.
    speed= distance divided by time so \frac{x}{t}= 2. that is equivalent to x= 2t.

    After school she jogs back home at 6km/h and saves 15mins. how far does Dahlia live from school?
    So \frac{x}{t- 1/4}= 6. That is equivalent to x= 6(t- 1/4). Together with x= 2t, x= 2t= 6t(t- 1/4). Solve that for t then use x= 2t to find x.

    Thanks!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,909
    Thanks
    771

    Re: Linear equations question grade 10

    Hello, xXplosionZz!

    Dahlia walks from her house to school at 2km/h.
    After school she jogs back home at 6km/h and saves 15mins.
    How far does Dahlia live from school?

    Recall the formula: . \text{Distance} \:=\:\text{Speed} \times \text{Time}
    . . We have: . D \:=\:S\cdot T \quad\Rightarrow\quad T \:=\:\frac{D}{S}


    Let x = distance to school (in kilometers).

    She walks x km at 2 km/h.. This takes: \tfrac{x}{2} hours.

    She jogs x km at 6 km/h.. This takes: \tfrac{x}{6} hours.


    Her jogging time is a \tfrac{1}{4}-hour less than her walking time.

    Our equation is: . \frac{x}{6} \;=\;\frac{x}{2} - \frac{1}{4}

    Go for it!
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Oct 2012
    From
    Canada
    Posts
    15

    Re: Linear equations question grade 10

    Thanks everyone, I got it!
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Super Member
    Joined
    Nov 2007
    From
    Trumbull Ct
    Posts
    917
    Thanks
    27

    Re: Linear equations question grade 10

    another way

    km/hr x hr = km
    2t1 =d=6t2
    t1=3t2
    t1-t2=1/4
    3t2-t2=1/4
    t2 = 1/8 hr
    d=6/8 =3/4 km
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Grade 9 Equations with Fractions
    Posted in the Algebra Forum
    Replies: 5
    Last Post: June 11th 2012, 02:29 PM
  2. Grade 9 Equations with Fractions 2
    Posted in the Algebra Forum
    Replies: 1
    Last Post: June 11th 2012, 11:09 AM
  3. I need help with a 2nd grade equations
    Posted in the Algebra Forum
    Replies: 7
    Last Post: September 2nd 2011, 03:16 PM
  4. Challenging grade 6 question or grade 9 ?
    Posted in the Algebra Forum
    Replies: 2
    Last Post: June 24th 2010, 11:04 AM
  5. urgent help in math grade 10 linear equations
    Posted in the Algebra Forum
    Replies: 6
    Last Post: January 19th 2009, 03:27 PM

Search Tags


/mathhelpforum @mathhelpforum