Объяснение:

2,5(0,2+x)-0,5(x-0,7)-0,2=0,5

0,5+2,5x-0,5x+0,35-0,2-0,5=0

2x=-0,15

x=0,075

1/4(2-3x)=3/8(x+1)-1

1/2-3x/4=3x/8+3/8-1

-3x/4-3x/8=3/8-1-1/2

-9/8x=-9/8

x=1

Ответ:(5/2×1/5+5/2х)-(1/2х-1/2×7/10)=(25/10×2/10+5/2х)-(1/2х-5/10×7/10)=(5+2.5х)-(0.5х-3.5)=5+2.5х-0.5х+3.5=8.5+2х.

8.5+2х=0.5

2х=-8

Х=-4

Объяснение:1/4(2-3х)=3/8(х+1)-1

2/4-3/4х=3/8х+3/8-1

2/4-3/8+1=3/8х+3/4х

1+1/8=9/8х

(1+1/8)=(1+1/8)х

Х=(1+1/8)/(1+1/8)

Х=1