[tex]\displaystyle \\
\log_{2}(x^2 + 3x -10) = 3 \\ \\
x^2 + 3x -10 = 2^3 \\ \\
x^2 + 3x -10 = 8 \\ \\
x^2 + 3x -10- 8=0 \\ \\
x^2 + 3x -18=0 \\ \\
x_{12}= \frac{-3 \pm \sqrt{3^2 + 4\cdot18} }{2} = \\ \\
= \frac{-3 \pm \sqrt{9 + 72} }{2} = \frac{-3 \pm \sqrt{81} }{2} =\frac{-3 \pm 9}{2} \\ \\
x_1 = \frac{-3 + 9}{2} = \frac{6}{2} = \boxed{3} \\ \\
x_2 = \frac{-3 - 9}{2} = \frac{-12}{2} = \boxed{-6} \\ \\ [/tex]
