x/45+x/40+1/6=9/4 mn làm hộ em vs em cam ơn

$\frac{x}{45}+\frac{x}{40}+\frac{1}{6}=\frac{9}{4}$

$⇔\frac{x}{45}+\frac{x}{40}+\frac{1}{6}=\frac{9}{4}$

$⇔\frac{8x}{360}+\frac{9x}{360}+\frac{60}{360}=\frac{810}{360}$

$⇔\frac{8x+9x+60-810}{360}=0$

$⇔17x-750=0$

$⇔17x=750$

$⇔x=\frac{750}{17}$