2a-8a=12-8a
now add 8a to both side and you get
2a= 12
divide both sides by 2 and you get
a=6
Answer:

Step-by-step explanation:
Hello There!
First thing we want to do is find the formula for circumference of a circle
C = 2(3.14)r
where r = radius
we are given the diameter so we have to convert that into radius to do so we just divide by 2
42/2=21 so the radius equals 21 inches
now we just plug in 21 for r in the formula

So we can conclude that the circumference of the circle is 131.88 inches
Answer:
C. ????
Step-by-step explanation:
Check the picture below.
make sure your calculator is in Degree mode.
M-6 is the expression that shows how far Allison has to run