Which equation has exactly one solution?

7
x
=
7
7 x is equal to 7

7
x
=
7
x
7 x is equal to 7 x

x
+
1
=
x
+
1
x plus 1 is equal to x plus 1

x
+
1
=
x
+
2

Which equation has exactly one solution 7 x 7 7 x is equal to 7 7 x 7 x 7 x is equal to 7 x x 1 x 1 x plus 1 is equal to x plus 1 x 1 x 2 class=