Advanced Math practice question

Answer: 4

√(x + 5) = 5 − √x; squaring gives x + 5 = 25 − 10√x + x, so √x = 2 and x = 4.

Common wrong answers

If you answered 2

2 is √x, not x.

If you answered 16

16 comes from √x = 4.

If you answered 20

20 comes from 10√x = 20 read as x = 20.

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