log,a log, (log: (x-15)] = 0, then x-
Answers
Answered by
0
Answer:
-=
=+
=
..............
Answered by
0
Step-by-step explanation:
Put everything that's a log on the same side
log
(
x
−
15
)
+
log
(
x
)
=
2
Remember that
log
(
m
)
+
log
(
n
)
=
log
(
m
n
)
log
(
x
(
x
−
15
)
)
=
2
If
log
a
(
b
)
=
c
, then
b
=
a
c
x
(
x
−
15
)
=
10
2
Expand and solve the quadratic equation
x
2
−
15
x
=
100
→
x
2
−
15
x
−
100
=
0
x
=
15
±
√
225
−
4
⋅
1
(
−
100
)
2
=
15
±
√
225
+
400
2
x
=
15
±
√
625
2
=
15
±
25
2
x
1
=
15
+
25
2
=
40
2
=
20
x
2
=
15
−
25
2
=
−
10
2
=
−
5
Remember that since we were dealing with logarithms, we can't have null or negative arguments, so
x
−
15
>
0
→
x
>
15
x
>
0
We conclude that any answers must follow
x
>
15
, which only of the two answers do, thus, the answer is
x
=
20
if you have =2 inplace of =0
...HOPE YOU WILL UNDERSTAND.. !
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