Answer:
Step-by-step explanation:
See a solution process below:
Step-by-step explanation:
Step 1) Solve the second equation for 
x
:
2
x
−
2
y
=
18
2
x
−
2
y
+
2
y
=
18
+
2
y
2
x
−
0
=
18
+
2
y
2
x
=
18
+
2
y
2
x
2
=
18
+
2
y
2
2
x
2
=
18
2
+
2
y
2
x
=
9
+
y
Step 2) Substitute 
(
9
+
y
)
 for 
x
 in the first equation and solve for 
y
:
4
x
+
3
y
=
−
13
 becomes:
4
(
9
+
y
)
+
3
y
=
−
13
(
4
×
9
)
+
(
4
×
y
)
+
3
y
=
−
13
36
+
4
y
+
3
y
=
−
13
36
+
(
4
+
3
)
y
=
−
13
36
+
7
y
=
−
13
−
36
+
36
+
7
y
=
−
36
−
13
0
+
7
y
=
−
49
7
y
=
−
49
7
y
7
=
−
49
7
7
y
7
=
−
7
y
=
−
7
Step 3) Substitute 
−
7
 for 
y
 in the solution to the second equation at the end of Step 1 and calculate 
x
:
x
=
9
+
y
 becomes:
x
=
9
−
7
x
=
2
The solution is: 
x
=
2
 and 
y
=
−
7
 or 
(
2
,
−
7
)
The solution is: 
x
=
2
 and 
y
=
−
7
 or 
(
2
,
−
7
)