Частина 2 — Вправи: 1277(1-4)

1277. Розв’яжіть рівняння:

1) 2,5х = –1;х = –1 : 2,5;х = –0,4.

2) 0,3х = 1;х = 1 : 0,3;х = 313.

3) 7х = –3;х = –3 : 7;х = –37.

4) –16х =8;х = 8 : (–16);х = –0,5.

5) |х| – 5 = 0;х = 5;х = 5;або х = –5.	6) |х| + 3,2 = 8|х| = 4,8;х = 4,8або х = –4,8.	7) 4,1 –|х| = 5;|х| = –0,9.розв’язківнемає.	8) |3х + 8| = 0Зх + 8 = 0;Зх = –8;х = –223.
9) 9|х| – 6 = 0;9|х| = 6;|х| = 23;х = 23 або х=–23	10) 8х = 65;6х = 40;х = 623.	11) 74 = х2;4х = 14;х = 3,5;х = 13.	12) х + 312 = 43;3(х + 3) = 48;х + 3 = 16.

13) 7х = х +25;6х = 25;х = 416.	14) 0,4х – 6 = 0,6х – 9;0,2х = 3;х = 15.
15) 3х + 16 = 9 – 10х;13х = –7;х = – 713.	16) 0,6 (х + 123) = –1,2;х + 123 = –2;х = –2 – 123;х = –323.

17) –3,4 (х + 9311) = –68;х + 9311 = 20;х = 191111 – 9311;х = 10811.	18) х3 + х4 = –21;7х12 = –21;х = –21 : 7 ∙ 12;х = –36.
19) 2m3 – 4m5 = 3;– 2m15 = 3;m = 3 ∙ 15 : (–2);m = –2212.	20) 4a9 – 1 = 5a12;16a36 – 15a36 = 1;a36 = 1;a = 36.

21) 3(1 – x) + 5(х + 2) = 1 – 4х;3 – 3х + 5х + 10 = 1 – 4х;6х = –12;х = –2.	22) 3(2 –х) – (5х + 4) = 0,4 – 16х;6 – 3х – 5х – 4 = 0,4 – 16х;8х = –1,6;х = –0,2.
23) 2(3 – 5р) = 4(1 –р) –1;6 – 10р = 4 – 4р – 1;6р = 3;р = 0,5.	24) 0,5 (2у–1) – (0,5– 0,2у) + 1 = 0;у – 0,5 – 0,5 + 0,2у + 1 = 0;1,2у = 0;у = 0.

25) –4(5 – 2m) + 3(m – 4) = 6(2 – m) – 5m;

–20 + 8m + 3m – 12 = 12 – 6m – 5m;

22m = 44;

m = 2.

26) 0,3(3х– 1) + 0,2 = 5(0,1 – 0,2х) – 0,1;

0,9х – 0,3 + 0,2 = 0 ,5 – х – 0,1;

1,9х = 0,5;

x = 519.