Alex asked in Science & MathematicsPhysics · 9 years ago

find a. given that y = k / (ax +2) and that y = 10 when x = 5 and y = 3.75 when x = 14?

Update:

Could you show step wise working out of the problem?

4 Answers

Relevance
  • iceman
    Lv 7
    9 years ago
    Favorite Answer

    k/(5a + 2) = 10

    k/(14a + 2) = 3.75

    k = 10 (5a + 2)

    k = 3.75 (14a + 2)

    50a + 20 = 52.5 + 7.5

    2.5a = 12.5

    a = 5

    • Login to reply the answers
  • 9 years ago

    y = k / (ax +2).....................(1)

    Putting y=10 and x=5 in equation (1)---->

    10 =k / (a*5 +2)

    10 =k / (5a +2)

    5a+2= k/10

    50a+20=k--------------(2)

    Again putting y=3.75 and x=14 in equation (1)------->

    3.75 =k / (a*14 +2)

    3.75 =k / (14a +2)

    14a+2 =k/ 3.75

    14*3.75 a+ 2*3.75 = k

    52.5 a+7.5 = k -----------(3)

    From equations (2) and (3),

    50a+20 = 52.5 a+ 7.5

    2.5 a = 12.5

    a = 12.5/2.5 = 5

    So a= 5

    • Login to reply the answers
  • u.n. o
    Lv 5
    9 years ago

    y(ax+2) = k

    10(5a+2) = k

    3.75(14a+2) = k

    2.5a = 12.5

    a = 5

    • Login to reply the answers
  • 9 years ago

    put the values and get the two equations in a and k.

    answer should be a=5

    • Login to reply the answers
Still have questions? Get your answers by asking now.