sophieMoney sophieMoney
  • 21-11-2016
  • Mathematics
contestada

solve for x. 27^(2x)=9^(x-3) ...?

Respuesta :

JcAlmighty
JcAlmighty JcAlmighty
  • 23-11-2016
The answer is [tex]x = - \frac{4}{3} [/tex]

[tex] 27^{2x} = 9^{(x-3)} \\ (3^{3} )^{2x} = (3^{2}) ^{(x-3)} \\ \\ (x^{a} )^{b}= x^{a*b} \\  3^{3*2x} =3^{2*(x-3)} \\ 3^{6x} =3^{(2x-6)} [/tex]

Now, logarithm both sides of the equation:
[tex]log(3^{6x} )=log(3^{(2x-6)}) \\ \\ log (x^{a}) =a*log(x) \\ 6x*log(3)=(2x-6)*log(3)[/tex]

Divide both sides of the equation by log(3):
[tex]6x=2x-6 \\ 6x-2x = -6 \\ 4x = -3 \\ x = - \frac{4}{3} [/tex]
Answer Link

Otras preguntas

What national symbol is common to China and Wales ?
write a paragraph on my favourite teacher
resources are an integral part of human survival.yet indiscriminate use of them by humans has led to a crisis situation."discuss the above ststement in light of
if the minimum velocity of a projectile is double the minimum velocity,the angle of projection is
Relationship between Mini and Kabuliwala
write a paragraph on my favourite teacher
Collect information about working of geyser and prepare a report
true or false questions basic math 1.the total surface area of a cube each of whose edges is 12 inches long is 6 square feet 2.if the tank in a car holds 15 gal
how do u express a ratio as a decimal
what is the gcf and lcm of 390 and 250