The equations are
\ Equaton(1)
Equaton(2)
Substitute for y in the Equation (2).
Apply subtraction property of equality; if , then
.
(Subtract x from each side).
(Subtract:
).
Apply addition property of equality; if , then
.
(Add 4 to each side)
(Add:
)
(Divide each side by 2)
(Divide:
)
Substitute 4 for x in equation (2).
\ (Add:
)
The solution is .