Solution: 2x+7x=5+ 13

9x= 18

x=2

(3x+ 16)/2=4x-7

Solution: 3x+ 16=2(4x-7)

3x+ 16=8x- 14

8x-3x= 16+ 14

5x=30

x=6

(5y- 1 1)/7 =( 1 1y+3)/2 1

Solution: 21[(5y-11)/7] = 21[(11y+3)/21].

3(5y- 1 1)= 1 1y+3

15y-33= 1 1y+3

33+3= 15y- 1 1y

4y=36

y=9

27%x- 17%=20%x+ 1/4

Solution:100 (27% x-17%) =100 (20% x+1/4).

27x- 17=20x+25

27x-20x= 17+25

7x=42

x=6