Respuesta :

Answer:

[tex]\frac{f}{2} +9=4[/tex]

Subtract 9 from both sides:

[tex]\frac{f}{2}+9-9=4-9[/tex]

[tex]\frac{f}{2} =-5[/tex]

Multiply both sides by 2:

[tex]2*\frac{f}{2} =-5*2[/tex]

[tex]f=-10[/tex]