URGENT!!Imi trebuie pana la 9:30!ex15. Dau coroana!

Răspuns:

Explicație pas cu pas:

a)x+1/5=1/4     x=1/4-1/5      x=1/20

b)15/10(x+2/9)=225/100      x+2/9=15/10=3/2     x=3/2-2/9=(27-4)18=23/18

c)x-1=7/4×9/14      x-1=9/8      x=17/8

d)x+1/7=15×4/3     x+1/7=20     x=20-1/7=140-1/7=139/7

e)x-1/2=12×5/6    x-1/2=10  ⇒x=21/10

f)x-1/2=15/14×7/3     x-1/2=5/2⇒ x=6/2     x=3

a) 7(x +1/5)=1 3/4=7/4

7x+7/5=7

7x=7-7/5

7x=28/5

x=4/5=0,8

b) 1,5(x+2/9)=2,25

3,375(x+2/9)

27/8(x+2/9)

27/8×3/4

3,375x+0,75

c) 14/9(x-1)=7/4

x-1=9/8

x=9/8+1

x=17/8=2,125

d) 3/4(x+1/7)=15

x+1/7=20

x=20-1/7

x=139/7

e)6/5(x-0,5)=12

x-0,5=10

x=10+0,5

x=10,5

f)3/7(x-1/2)=15/14

x-1/2=5/2

x=5/2+1/2

x=3