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

2 Answers
Nov 20, 2016

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

Nov 21, 2016

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