How do you solve #abs(7-y)=4#?

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Answer 1 · 2018-04-04T00:23:09

y = 3 and y = 11

Because we are taking the absolute value of #7-y#, we set up two equations that correspond to the negative and positive outcomes of #|7-y|#

#7-y = 4#
and
#-(7-y) = 4#

This is because taking the absolute value of both equations will yield the same answer. Now all we do is solve for y in both cases

#7-y=4; y = 3#

and

#-7+y=4; y = 11#

We can plug both values into the original function to demonstrate this.

#|7-(3)| = 4#

#|7-(11)|=4#

Both cases are true, and we have two solutions for y