Respuesta :

Answer:

Step-by-step explanation:

let f(x)=y

y=2x+5

flip x and y

x=2y+5

2y=x-5

y=(x-5)/2

f^{_1}(x)=(x-5)/2

but f^{-1}(x)=1

so (x-5)/2=1

x-5=2

x=2+5=7