Answer:
p=21.4
P= 44.43 degrees
Explanation:
This is Pythagorean's theorem! Remember a^2+b^2=c^2
so with our numbers, c=30, b=21, and we need to solve for a...
a^2+21^2=30^2
a^2=30^2-21^2
a=sqrt(30^2-21^2)
so...
a= 21.4 cm (rounded to the tenth)
now for the angle P, lets use some trig
we know that sin(P)=21/30
so we can determine that
P=arcsin(21/30)
P= 44.43 degrees