Question 188634
ab can be written as 10a+b.....ba can be written as 10b+a
:
10a+b=7(a+b)-3.........eq 1--->10a+b=7a+7b-3--->3a-6b=-3
10b+a=10a+b-18.........eq 2------------------->-9a+9b=-18
:
3a-6b=-3......revised eq 1
-9a+9b=-18.....revised eq 2
:
multiply eq 1 by 3 and add the two equations together. a terms will be eliminated and we are left with -18b+9b=-9-18
:
-9b=-27
:
b=3
:
plug b's value into any equation ...I chose revised eq 1
3a-6(3)=-3
:
3a=15
:
a=5
:
original number is 53