Maths problem. Please help.?

How can I make

n-6/n * n-7/n-1 = 1/2

into

n^2 - 25n + 84 = 0

I totally don't understand this so please please help.

Update:

and by n-7/n-1 i mean (n-7)/(n-1)

Comments

  • Multiply both sides of the equation with 2n(n-1). This then evaluates to:

    2(n-6) * (n-7) = n(n-1)

    2(n^2 - 7n -6n + 42) = n^2 -n

    2n^2 - n^2 - 14n -12n +n +84 = 0

    n^2 -25n +84 = 0

    q.e.d

  • Multiply the top (n-6)(n-7)= n^2 -13n + 42

    multiply the bottom n(n-1)= n^2- n

    Then cross multiply with 1/2 to get

    2n^2 - 26n + 84= n^2 - n

    When u move the items from right to the left, u change the signs and you will get n^2 - 25n + 84= 0 which is what u r looking for.

  • n -6/n =(n-6)/n or n-(6/n) ? frame your expressions using parenthesis ...we dont understand your q

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