Question

Tìm x:

\(\frac{\left(-3\right)^x}{81}=-27\)Giup mik nhé!mik tik cho!

Answer 1

(-3)^x/81=-27

(-3)^x:(-3)^4=(-3)^3

(-3)^x=(-3)^3.(-3)^4

(-3)^x=(-3)^7

suy ra x=7

vậy x=7

Answer 2

\(\frac{\left(-3\right)^x}{81}=-27\)

\(\Rightarrow\left(-3\right)^x=-27.81=-2187\)

\(\Rightarrow\left(-3\right)^x=\left(-3\right)^7\)

\(\Rightarrow x=7\)