1) 7Х+42 =20Х+16
7Х-20Х = -42 +16
- 13Х = -26
13Х = 26
<u>Х= 2</u><u />
2)1,5Х + 12 = -4Х +1
1,5Х + 4Х = -12 +1
5,5 Х = - 11
<u> </u><u> Х = - 2</u>
3) 0,75Х + 6 = 2Х +1 (т.к. 3/4 = 0,75)
0,75Х - 2Х = -6 +1
- 1,25Х = -5
1,25Х = 5
<u>Х = 4</u>
14·5=70 3·16=48 4·22=88 25·2-25=25
5*(8е-1)-28е=19
40е-5-28е=19
40е-28е=19+5
12е=24
е=24:12
е=2