-8(1 + 8n) - 8(6 - 4n) = -24
-8 - 64n - 48 + 32n = -24
-32n - 56 = -24
-32n = 32
n = -1
(3x+4)+(5x2-1)+(2x+6)
remove unnecessary parenthesis
3x+4+(5x2-1)+(2x+6)
3x+4+(10-1)+2x+6
subtract the numbers
3x+4+9+2x+6
collect the like terms
5x+4+4+9+6
5x+19
Answer - to solve for the equivalent equation of r you would need to use the formula r=c/pi2.
I think that may be a trick question because all the the numbers can be on the number line