Question 518110
Kathy's age = K
Cat's age = C
.
K = C +6
.
Next year...
K+1
C+1
K+1 = 2(C+1)
.
Substitute K =C+6
.
C+6 +1 = 2(C+1)
C+7 = 2C +2
-C = -5
C = 5
.
The cat is 5 years old.
so
Kathy is 11 years old (5+6=11).
.
Next year, Kathy will be 12 and the cat will be 6, so Kathy will be twice the cat's age.
.
Done.