\(243-4x=3^9\div3^6\)
\(243-4x=3^3\)
\(243-4x=27\)
\(4x=243-27\)
\(4x=216\)
\(x=216\div4\)
\(x=54\)
\(5^x\div5^2=125\)
\(5^{x-2}=5^3\)
\(\Rightarrow x-2=3\)
\(\Leftrightarrow x=5\)
\(\left(x-30\right)\div2-150=10\)
\(\left(x-30\right)\div2=160\)
\(x-30=320\)
\(x=290\)
\(100-3x^2=76\)
\(3x^2=100-76\)
\(3x^2=24\)
\(x^2=8\)
\(\orbr{\begin{cases}x=\sqrt{8}\\x=-\sqrt{8}\end{cases}}\)
a) 243 - 4x = 3^9 : 3^6
=> 243 - 4x = 33
=> 243 - 4x = 27
=> 4x = 216
=> x = 54
b) 5^x : 5^2 = 125
=> 5x - 2 = 53
=> x - 2 = 3
=> x = 5
c) ( x - 30 ) : 2 - 150 = 10
=> (x - 30) : 2 = 160
=> x - 30 = 320
=> x = 350
d) 100 - 3x^2 = 76
=> 3x^2 = 24
=> x^2 = 8
=> x = \(\pm\sqrt{8}\)
