Step-by-step explanation:
First equation can be arranged as:
4
x
−
7
=
y
Put this y into the second equation (instead of y use
4
x
−
7
):
2
x
−
3
(
4
x
−
7
)
=
−
9
2
x
−
12
x
+
21
=
−
9
−
10
x
=
−
9
−
21
−
10
x
=
−
30
x
=
3
y can be obtained using the first equation:
y
=
4
x
−
7
y
=
(
4
×
3
)
−
7
y
=
12
−
7
y
=
5
Your solution
x
=
3