Answer:
x = 19/2 and y = 11/2
Step-by-step explanation:
change equation to look like:
x + y = 15 and x = 4 + y
substitute x in the first equation for 4 + y in the second equation
(4 + y) + y = 15
combine like terms
2y = 11
solve for y
y = 11/2
plug in y in the second equation
x = 4 + 11/2
make a common denominator
x = 8/2 +11/2
add
x = 19/2