Respuesta :

Answer:

1/28

Step-by-step explanation:

The expression is 7x-4y

  • x = 1/4
  • y= 3/7

Replace x by 1/4 and y by 3/7

  • 7x-4y
  • 7*([tex]\frac{1}{4}[/tex]) - 4*([tex]\frac{3}{7}[/tex])         multiply 1 by 7 and 4 by 3
  • [tex]\frac{7}{4}[/tex] - [tex]\frac{12}{7}[/tex]              multiply 7/4 by 7 and 12/7 ny 4 to get the same denominator
  • [tex]\frac{49-48}{28}[/tex]
  • 1/28