Well the sum is 15+6=21. then you must do 81-21=60. So your answer must be t=60.
Answer:
The perimeter of the triangle is 
Step-by-step explanation:
Let

we know that
The perimeter of triangle is equal to

the formula to calculate the distance between two points is equal to
step 1
Find the distance AB

substitute in the formula
step 2
Find the distance BC

substitute in the formula
step 3
Find the distance AC

substitute in the formula
step 4
Find the perimeter

substitute the values

Answer:
C
Step-by-step explanation:
Since there are two arcs and they both make up a circle, and a circle has 360 degrees.
NPL+NL=360
The measure of NPL is twice the measure of NL so
it now
2NL=NPL
Substitute that in the equation
2NL+NL=360
3NL=360
NL=120
Since NL subtends NML they are equal so NML=120