
Daniel D. answered 02/07/19
How can I help?
To answer this question, we need to consider what is known and what is currently unknown.
Known: 38 total Super Bowls
Unknown: the number won by each of two conferences
These unknowns can be represented as with variables to serve as placeholders until their values are known. I will use a and n. To have the total, a is being added to n.
a + n = 38
The NFC has won two more games than the AFC. This means that if we add two to the number of games won by the AFC then it should equal the number of games won by the NFC.
n = a + 2
The system of equations derived is the following:
a + n = 38
n = a + 2
Since a variable is already isolated, substitution would be an excellent method for finding the solution. Plug "a+2" in for n.
a + (a+2) = 38
Combine like terms.
a + (a+2) = 38
a + a + 2 = 38
2a + 2 = 38
Solve the two-step equation. 1) add or subtract 2) multiply or divide
Subtract the two from both sides.
2a = 36
Divide by two on both sides.
a = 18
The AFC has won 18 games. Any of the two equations in the system can be chosen to find the next solution. In a system, a solution is only a true solution if it is true for both equations. I will use the second one as it is already set equal to n.
n = a + 2
n = 18 + 2
n = 20
The NFC won 20 games.