5 . ( x-3 ) -18 = 2
5x - 15 = 2 + 18
5x - 15 = 20
5x = 20 + 15
5x = 35
x= 7
Vậy x= 7
\(5x^2-15x-18=2\)
\(5x^2-15x-20=0\)
\(5\left(x^2-3x-4\right)\)\(=0\)
\(5\left(x^2-2xX\frac{3}{2}+\frac{9}{4}-\frac{9}{4}-4\right)=0\)
\(5\) {\(\left(x-\frac{3}{2}\right)^2-\frac{25}{4}\)} \(=0\)
\(\left(x-\frac{3}{2}\right)^2\) \(=\frac{25}{4}\)
\(x=\frac{\sqrt{25}}{2}+\frac{3}{2}\) hoặc \(x=\frac{-\sqrt{25}}{2}+\frac{3}{2}\)
\(\frac{x}{23}+45=597037\)
\(\frac{x}{23}=596992\)
\(x=13730816\)
Bài 1 :
\(5\cdot\left(x-3\right)-18=2\)
\(5x-15-18=2\)
\(5x-15=2+18\)
\(5x-15=20\)
\(5x=20+15\)
\(5x=35\)
\(x=35:5\)
\(x=7\)
Bài 2 :
\(\left(x:23+45\right):67=8911\)
\(x:23+45=8911:67\)
\(x:23+45=133\)
\(x:23=133-45\)
\(x:23=88\)
\(x=88\cdot23\)
\(x=2024\)
