Řeš v ℝ rovnice pomocí rozkladu na součin:
\large x^{2} + 2 x-8 = 0
K = \left\{ { – 4;\ \left. 2 \right\}} \right.
K = \left\{ { – 5;\ \left. 2 \right\}} \right.
K = \left\{ { – 3;\ \left. 2 \right\}} \right.
K = \left\{ { – 4;\ \left. 3 \right\}} \right.