The sum of the ages of two brothers is 37.7 years. The older brother is
7.9 years older than the younger brother. The line graphed on the
coordinate grid represents the first of two equations in a system of linear
equations that can be used to find their ages.


If the second equation is x+y=37.7 , which value is closest to x, the age of the older brother in years?


a. 8
b. 15
c. 23
d. 30