Question

Kris solved the radical equation 15−x−−−−−√+x=3
and found that x=−1
or x=6
.

Which statement correctly describes the solution set of the radical equation?

(1 point)

x=−1
or x=−6


x=−1


x=−1
or x=6


x=1

Answer 1

Check each candidate in the original equation sqrt(15 − x) + x = 3.

- For x = −1: sqrt(15 − (−1)) + (−1) = sqrt(16) − 1 = 4 − 1 = 3 ✔
- For x = 6: sqrt(15 − 6) + 6 = sqrt(9) + 6 = 3 + 6 = 9 ✖

So x = 6 is extraneous (introduced when squaring). The solution set is x = −1.