Answer
(a) See the graph.
(b)
$y=x+2$
Work Step by Step
(a) Both $x=t^2-1$ and $y=t^2+1$ are quadratic functions. Their minimum occurs when $t=0$ in which $x=-1$ and $y=1$. So, in the point $(-1,1)$ the function changes the direction.
(b)
$x=t^2-1$
$t^2=x+1$
$y=t^2+1$
$y=x+1+1$
$y=x+2$
