Answer:
x
2
+
12
x
−
64
=
0
⟹
x
2
+
12
x
=
64.
x
2
+
12
x
=
64
⟹
(
4
∗
1
)
(
x
2
+
12
x
)
=
(
4
∗
1
)
64
⟹
4
x
2
+
48
x
=
256
All this is straight forward. This method now requires you to add the square of the original coefficient of x to both sides of the equation.
The original coefficient is 12 so its square is 144.
4
x
2
+
48
x
=
256
⟹
4
x
2
+
48
x
+
144
=
256
+
144
=
400
⟹
4
(
x
2
+
12
x
+
36
)
=
20
2
⟹
2
2
(
x
+
6
)
2
=
20
2
.
Explanation: