maths problem, helpppp:)!!!!?

when a number is decreased by 7 and this result is divided by the sum of the number and 11, the answer is -3/4. find the number

how do i write out the formula for that

Comments

  • (x - 7) / (x + 11) = -3/4

    4 (x - 7) = -3 (x + 11)

    4x - 28 = -3x - 33

    4x + 3x - 28 + 33 = 0

    7x + 5 = 0

    x = -5/7

  • Let the number be N

    N is decreased by 7 and this result is divided by the sum of the number and 11, the answer is -3/4. Therefore:

    . .N – 7 . . . . 3

    ––––––– = - –– . . . . . . . . . <- cross multiply

    .N + 11 . . . . 4

    (N – 7)(4) = -3(N + 11)

    4N – 28 = -3N – 33 . . . . . . <- rearrange

    4N + 3N = -33 + 28

    7N = -5 . . . . . . . . . . . . . . .<- divide both sides by 7

    . . . . .5

    N = - ––

    . . . . .7

    Done

  • Let the number be x

    number is decreased by 7, so, x-7

    sum of the number and 11 = x+11

    x-7 is divided by x+11, the answer is -3/4

    (x-7)/(x+11) = -3/4 This is the formula

    4x-28 = -3x - 33

    4x+3x = -33 +28

    7x = -5

    x= -5/7

    the number is -5/7

  • let n be the number

    (n-7)/(n+11) = -3/4

  • work backwards, start with -3/4, and say the number you are looking for is x

    therefore, -3/4= (x-7)/(x+11)

    hope that helps you a bit

  • Denote the width in cm by technique of w then the with width x length = section (the position l=length) we've wcm x (w+4)cm = 26cm^2 => w^2 + 4w = 26 ('Dividing' for the length of by technique of cmxcm and increasing) => w^2 + 4w - 26 = 0 making use of the nicely commonly used formula for fixing a^2 + bx + c = 0 ie x = (-b +/- sqrt(b^2 - 4ac))/2a with a = a million, b = 4 and c = -26 and x = w, we've w = (-4 +/- sqrt(4^2 - 4.a million.(-26)) / 2 = (-4 +/- sqrt(16 + 104)) / 2 = (-4 +/- sqrt(one hundred twenty)) / 2 = (-4 +/- 2sqrt(30))/2 = -2 + sqrt(30) or = -2 - sqrt(30) because the width w must be constructive, the in elementary words wise answer is w = (-2 + sqrt(30)) cm which makes l = (2 + sqrt(30)) cm (l = w+4, undergo in concepts) i will allow you examine the outcomes for your self.

  • equation is

    (x-7) / (x+11) = -3/4

    so 4x - 28 = -3x -33

    7x = -5

    x= -5/7

  • it might be this but im not sure

    (x-7)

    ------------- = -3/4

    (y+z=11)

  • you should start learning math

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