The answer is 4 units long
this question involves trig
sinx=p/h -----> some people have
cosx=b/h ----> curly brown hair
tanx=p/b -----> through proper brushing
we have p and h in this question so we can use the first formula

Answer:
5
Step-by-step explanation:
Lets recall what the pythagroens theorm is:
A^2+B^2=C^2. A and B are the side lengths(adjacent and opposite), while C is the longest sloped length(hyotenouse).
Lets plug in our values for each, and solve for the missing one:
12^3+b^2=13^2
Square each value(except for unknown):
144+b^2=169
Now get b alone(subtract 144 from both sides):
b^2=25
Now root both sides(removes the ^2):
b=5
This is your answer!
Hope this helps! :)