-2(x+2) =6 -ax In the equation shown above a is the constant. Which of the following values of a results in an equation with exactly one solution?

Use Negative Power Rule:
x
−
a
=
1
x
a
x
−a
=
x
a


1
.

Multiply both sides by
6
a
x
6
ax
. Divide both sides by
−
2
−2. Divide both sides by
x
+
2
x+2. Simplify
1
2
x
+
2
x+2

2

1

to
1
2
(
x
+
2
)
2(x+2)

1
. Use Definition of Common Logarithm and for last : Divide both sides by
x
x.