We notice that we can write 15 =
3*5
We'll raise to 2x-3 both
sides:
15^(2x-3) =
3^(2x-3)*5^(2x-3)
We'll re-write the
equation:
3^(2x-3)*5^(2x-3) =
3^x*5^(3x-6)
We'll divide by 3^x and we'll
get:
3^(2x-3)*5^(2x-3)/3^x =
5^(3x-6)
We'll divide by
5^(2x-3):
3^(2x-3)/3^x =
5^(3x-6)/5^(2x-3)
We'll subtract the
exponents:
3^(2x - 3 - x) = 5^(3x - 6 - 2x +
3)
We'll combine like terms inside
brackets:
3^(x - 3) = 5^(x -
3)
We'll re-write the
equation:
3^x*3^-3 =
5^x*5^-3
3^x/3^3 =
5^x/5^3
We'll create matching bases. We'll divide by
5^x:
3^x/5^x*3^3 = 1/5^3
We'll
multiply by 3^3:
3^x/5^x =
3^3/5^3
(3/5)^x =
(3/5)^3
Since the bases are matching, we'll apply one to
one property:
x =
3
The solution of the equation is x =
3.
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