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

2 Answers
Atila Ç. · EZ as pi
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 #

EZ as pi
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#

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