Anonymous
Anonymous asked in Science & MathematicsMathematics · 1 decade ago

Can someone please solve for V in this equation?

600 / ( V + 30 ) + 600 / ( V - 30 ) = 4.5

4 Answers

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  • 1 decade ago
    Best Answer

    600/(v+30) + 600/(v-30) = 4.5

    600[1/(v+30) + 1(v-30)] = 4.5

    multiply with (v^2 - 900)

    600[v-30 + v + 30] = 4.5(v^2-900)

    600[2v] = 4.5v^2 - 4050

    4.5v^2 - 1200v - 4050 = 0

    multiply with 2

    9v^2 - 2400v - 8100 = 0

    9v^2 - 2430v + 30v - 8100 = 0

    9v(v - 270) + 30(v - 270) = 0

    (v-270)(9v + 30) = 0

    v = 270 or -10/3

  • Harris
    Lv 6
    1 decade ago

    by putting both numbers under 1, like this,

    1/(600/(v+30)+600/(v-30))=1/(4.5)

    we get:

    (v+30)/600+(v-30)/600=1/4.5

    since the denominator is the same,

    ((v+30)+(v-30))/600=1/4.5

    2v/600=1/4.5

    *600 on both sides results:

    2v=600/4.5

    then divide by 2 to get:

    v=600/9

    v=66 2/3

  • 1 decade ago

    600 / (V+30) + 600 / (V-30) = 4.5

    Multiply by (V+30)(V-30) = V² – 900

    600(V-30) + 600(V+30) = 4.5 (V² – 900)

    600V-18000 + 600V +18000 = 4.5 V² – 4050

    1200 V = 4.5 V² – 4050

    4.5 V² -1200V – 4050

    Use –b ± √ [( b )² – 4(ac) ] / 2a

    -(-1200) ±√ [140000+72900] / 9

    1200 ± 1230 / 9

    V= -3.33

    V= 270

  • Kemmy
    Lv 6
    1 decade ago

    [600(V-30) + 600(V+30)] / (V+30)(V-30) = 4.5

    600V - 18000 + 600V + 18000 = 4.5(V^2 - 900)

    0 = 4.5V^2 - 1200V - 4050

    Solve the quadratic equation using the formula.

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