The difficulty might be that Exercise #27 is in a textblock.

% Exercise #27

\beginquestion

\startquestion[ex:secqu.27]

$f(x)=\sqrt{x+5}$.

\stopquestion

\endquestion

\beginlonganswer[]

\startanswer

\stopanswer

\endlonganswer

\beginshortanswer[]

\startanswer

$\text{Domain}=[-5,\infty)=\{x:\,x\ge -5\}$

\startbuffer

%initialize scale

numeric u; 20u=2in;

%draw axes

\includeMPgraphic{1010_xy_axes_ti}

%define function

vardef f(expr x)=

sqrt(x+5)

enddef;

%create function path

path p; p:=(-5,f(-5));

for x=-5 step .1 until 10:

p:=p--(x,f(x));

endfor;

p:=p--(10,f(10));

p:=p scaled u;

drawarrow p withcolor blue;

label.rt(btex $\tfx f$ etex, (10,f(10)) scaled u);

%create projection domain

for x=-5 step 1 until 10:

drawarrow ((x,f(x))--(x,0)) scaled u withcolor green;

endfor;

pickup pencircle scaled 2pt;

drawarrow (-5u,0)--(10u,0) withcolor red;

pickup defaultpen;

filleddotred((-5u,0));

label.bot(btex $\tfx -5$ etex, (-5u,0));

\stopbuffer

\startlinecorrection[blank]

\midaligned{\processMPbuffer}

\stoplinecorrection

\column                   <--------------------Taco, inserting a column break works, which is what we'll probably do

$\text{Range}=\{y:\,y\ge 0\}=[0,\infty)$

\startbuffer

%initialize scale

numeric u; 20u=2in;

%draw axes

\includeMPgraphic{1010_xy_axes_ti}

%define function

vardef f(expr x)=

sqrt(x+5)

enddef;

%create function path

path p; p:=(-5,f(-5));

for x=-5 step .1 until 10:

p:=p--(x,f(x));

endfor;

p:=p--(10,f(10));

p:=p scaled u;

drawarrow p withcolor blue;

label.rt(btex $\tfx f$ etex, (10,f(10)) scaled u);

%create projection domain

for y=0 step 1 until 3:

drawarrow ((y*y-5,y)--(0,y)) scaled u withcolor green;

endfor;

for y=4 step 1 until 10:

drawarrow ((10,y)--(0,y)) scaled u withcolor green;

endfor;

pickup pencircle scaled 2pt;

drawarrow (0,0)--(0,10u) withcolor red;

pickup defaultpen;

filleddotred((0,0));

label.lft(btex $\tfx 0$ etex, (0,0));

\stopbuffer

\startlinecorrection[blank]

\midaligned{\processMPbuffer}

\stoplinecorrection

\stopanswer

\endshortanswer