Номер 1223

1) –1/2 • (х + 4) = 0

    х + 4 = 0

    х = 0 – 4

    х = –4

2) х • (х – 2) = 0

   х = 0 або х – 2 = 0

                х = 0 + 2

                х = 2

3) (х – 3) (х + 15) = 0;

    х – 3 = 0 або х + 15 = 0

    х = 0 + 3      х = 0 – 15

    х = 3           х = –15

4) | – 7|(х + 3) = 0

   |x – 7| = 0 або х + 3 = 0

    х – 7 = 0      х = 0 – 3

    х = 7           х = –3