Giúp e vs ạ e cần gấp

Giải thích các bước giải:

d.$\dfrac1{10}x-\dfrac52=\dfrac43$ 

$\to \dfrac1{10}x=\dfrac{23}6$

$\to x=\dfrac{115}3$

đ.$\dfrac{x-45}{55}+\dfrac{x-44}{56}+\dfrac{x-43}{57}+\dfrac{x-42}{56}=-5$

$\to (\dfrac{x}{55}+\dfrac{x}{56}+\dfrac{x}{57}+\dfrac{x}{56})=\dfrac{45}{55}+\dfrac{44}{56}+\dfrac{43}{57}+\dfrac{42}{56}-5$

$\to x\cdot (\dfrac{1}{55}+\dfrac{1}{56}+\dfrac{1}{57}+\dfrac{1}{56})=\dfrac{45}{55}+\dfrac{44}{56}+\dfrac{43}{57}+\dfrac{42}{56}-5$

$\to x=\dfrac{\dfrac{45}{55}+\dfrac{44}{56}+\dfrac{43}{57}+\dfrac{42}{56}-5}{\dfrac{1}{55}+\dfrac{1}{56}+\dfrac{1}{57}+\dfrac{1}{56}}$