Ответы и объяснения

2012-12-16T22:54:03+04:00

1.

4²=3х+1

16=3х+1

3х=15

х=5

2.

(1/8)*х - 7 = 2

(1/8)*х = 9

х = 72

3. 

lg(1-0,4x)=-2

lg(1-0,4x) = lg (1/100)

1-0,4x = 0,01

0,4x=0,99

x=9,9/4

4.

4x-3=9

4x=12

x=3

5.

(4x-6)/(4-2x)=2

4x-6=8-4x

8x=14

x=7/4

6.

log₃(12x-111)=6

log₃(12x-111) = log₃ 216

12х-111=216

12х=105

х=35/4

7.

log₃9х²=4

log₃9х²=log₃256

9х²=1856

х= 16/3