What's the question or what you are trying to find
Find two numbers with a sum of 20 and a difference of 14
Make two equations
X+Y=20
X-Y=14
Now add x since y cancels out and add 20+14 To end up with
2x=34
Now divide 2 both sides to get x alone
2x/2=34/2
X=17
Now substitute x answer to first equation and solve for y
17+y=20
Subtract 17 both sides
Y= 3
Your two numbers are
3 and 17
12 + n
if you substitute n for any whole number and simplify. you will find that 12+n does not equal any others. for example, i used 6 in place of n and all equations gives you 10 except 12+n
hope this helps!
The answer is:
[C]: 61.38 cm .
_______________________________________________Note: A =

²
300 = (3.14) * r² ;
______________________
Divide each side by "3.14" ;
r² = 300/3.14 ;
r² = 95.5414012738853503 ;
√r² = √(95.5414012738853503) ;
r = 9.7745281867661188048
Circumference, "C" =

* d ; (d = diameter = 2*r);
C = 2*

*r ;
C = 2*(3.14)*(9.7745281867661188048)
C = 61.384037012891226094144 ; which rounds to answer choice: [C]: 61.38 cm .________________________________________________________