Answer:
51
Step-by-step explanation:
y is the ten digit
and x the ones digit
y+x=6 -> x=6-y subtracted each side by y
2y+3=x
2y+3=6-y they both equal x so the equal each other
add y to both side to get rid of the y
minus 3 form both side to get rid of the 3
3y=3
y=1
plug it in
2(1)+3=x
5=x
51
