Respuesta :

18 - (-f) = 91

Subtracting a negative value changes to addition:

18 + f = 91

Subtract 18 from both sides:

F = 73

Answer:

f = 73

Step-by-step explanation:

Solve for f

18 - ( - f ) = 91

  • Remove the parantheses and change their sign.

18 + f = 91

  • subtract each side by 18

18 - 18 + f = 91 - 18

  • calculate

f = 73