EXPLANATION:
-To formulate an equation, you must first know what data the exercise gives us to locate them correctly.
data:
-6 that must be added to a number.
-four times a number that is equal to 4x
-a result that is equal to 50
Now with these data we formulate the equation:

if we solve the equation we have:
Answer:
x=10
Step-by-step explanation:
P+S=140
(5x+30)+80=140
5x+30=80
5x=50
x=10
First of all, let's recall that the full circumference is

Now, since 30 is one twelfth of 360, a 30° arc will be one twelfth of the whole circumference. So, if you call the arc length A, you have

Since we know the arc length, we can build and solve the following equation:
