can any one solve this one? 9-3(n-5)=30?

Update:

can any one tell me if the answers 18?

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  • 1 decade ago
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    step 1) expand the brackets

    9 - [3 * (n - 5)] = 30

    9 - [(3 * n) - (3 * 5)] = 30

    9 - [ 3n - 15 ] = 30

    a minus add a minus is a plus and so we get

    9 - 3n - - 15 = 30

    9 + 15 - 3n = 30

    24 - 3n = 30

    step 2) rearrange to find n and solve

    get the n's by themselves by adding 3n to each side

    and taking away 30

    24 - 3n + 3n = 30 + 3n

    24 = 30 + 3n

    24 - 30 = 3n

    -6 = 3n

    divide each side by 3 to get n on its own

    (-6/3) = (3n/3)

    -2 = n

    so this is the answer: n = -2

    we can check that this answer is right by putting it back into the equation

    9 - [3 * (n - 5)] = 30

    9 - [3 * ((-2) - 5)] = 30

    9 - [3 * (-7)] = 30

    9 - [-21] = 30

    as a minus add a minus equals a plus, we get

    9 + 21 = 30

    30 = 30 [ this is correct so we can be sure that n = -2 ]

  • 1 decade ago

    The answer is -2. 9-3n+15=30. Subtract 15 from each side: 9-3n=15. Then subtract 9: -3n=6. Divide by -3. n=-2.

  • 1 decade ago

    9-3(n-5)=30

    Distribute the -3 to (n-5)

    9-3n+15=30

    Combine the 9 and 15

    -3n + 24=30

    Subtract 24 from both sides

    -3n = 6

    Divide by -3

    n=-2

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