Answer
$\ 10244$
$\underline{-8534}$
$\ \ \ 1710$
Work Step by Step
$\ 10a4b$
$\underline{-85c4}$
$\ \ \ d7\underset\uparrow 10\ \leftarrow b-4=0\ so\ b=4$
$\ \ \ \ \ \ \ 4-c=1,so\ c=3$
$\ 10a44$
$\underline{-8534}$
$\ \ \ d\underset\uparrow 710$
$\ \ \ \ \ \ a-5=7.$ Since $7\gt5$ borrowing was done.
$\ \ \ \ \ \ a+10-5=7,\ so\ a=2$
$\ \ \ \overset9/\!\!\!\!\!10244$
$\underline{-8534}$
$\ \ \ \underset\uparrow d710$
$\ \ \ 9-8=d,\ so\ d=1$
