Question

How do you solve `\frac { n } { - 20} - 8= - 7`?

Answer 1

`n=-20`

Explanation:

`n/-20-8/1=-7/1`

Write each term with a denominator of `-20`

`n/-20-8/1xx(-20)/(-20)=-7/1 xx(-20)/(-20)`

`(n/-20)+(160/-20)=140/-20`

`:. n+160=140`

`n=140-160`

`n=-20`

Answer 2

`n =-20`

Explanation:

We note that there is a fraction, but because it is in an equation, you can get rid of the fraction altogether by multiplying each term by the LCM of the denominators.

`(cancel(-20)xxn)/cancel(-20) -8xx-20 = -7xx-20`

`n+160 = 140" "larr` subtract 160 from both sides.

`n = 140-160`

`n = -20`
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A quicker method would be to isolate the `n` term first.

`n/-20 - 8 = -7" "larr` add 8 to each side

`n/-20 = -7+8`

`n/-20 = 1" "larrxx-20`

`n= -20`