Chapter 10 - Radical Functions and Equations - 10.4 - Inverse of a Function - Exercises - Page 572: 11

$x=4y+4$ When output $y=2$, Input $x=12$.

$y=\frac{1}{4}x-1$ Adding $1$ to both sides, we get $y+1=\frac{1}{4}x-1+1$ $\implies y+1=\frac{1}{4}x$ Multiplying by $4$ on both sides, we get $4(y+1)=4\times\frac{1}{4}x$ $\implies x=4y+4$ When output $y=2$, Input $x=4(2)+4=12$