Respuesta :

Answer:

19. 3x+5/2x+7 =5

or, 3x+5=5×(2x + 7)

or, 3x + 5 = 10x + 35

or, 5 - 35 = 10x - 3x

or, -30 = 7x

or, -30/7 = x

21. let x be the other number

we know,

or, x × 1/7 =2

or, x/7 =2

or, x = 14

therefore, the other number is 14.