Tori's grandmother is five times older than she is. the sum of tori's and her grandmother age is 72. how old is tori

I think this is the answer + working out

x = Tori's age

y = her grandmother's age

x+y=72

5x=y

5x-y=0

x+y=72

+ (5x-y=0)

6x=72

72 divided by 6=

x=12

So Tori is 12 ...

We substitute 12 for x into the first equation ...

12+y=72

Bring 12 to the other side

y=72-12

y=60

Her grandmother is 60 and Tori is 12.