Question

Solve using the square root method. Round to the nearest tenth if necessary.
x^2 + 15 =0
A. {3.9}
B. {3.9, -3.9}
C. {7.5, -7.5}
D. no real solution

Answer 1

\[\Large x^2 + 15 = 0\]


\[\Large x^2 + 15-15 = 0-15\]


\[\Large x^2 = -15\]


\[\Large \sqrt{x^2} = \sqrt{-15}\]


\[\Large x = \sqrt{-15}\]


So there are no real solutions.

Answer 2

Subtract 15 from both sides and then take the square root of both sides.