How do you solve 21= | y + 685| + 621=|y+685|+6?

1 Answer
Thomas K.
Apr 12, 2018

y=-670y=−670

Explanation:

Since everything inside of the absolute value bars (|y+685||y+685|) is already positive there is no need for them anymore:
21=y+685+621=y+685+6
Next add:
21=y+69121=y+691
Then subtract:
y=-670y=−670
Check by putting it back in:
21=|-670+685|+621=|−670+685|+6
Solve absolute value bars first:
21=|15|+621=|15|+6
Then Solve:
21=2121=21
Works

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