You can
put this solution on YOUR website!Let

= number of children's tickets sold
Let

= number of adult tickets sold
Let

= number of senior tickets sold
given:
(1)

(2)

(3)

-----------------------
Substitute (1) and (2) into (3)
(3)

(3)

(3)

(3)

and, since
(2)

(2)

also
(1)

(1)

(1)

Linda sold
65 children's tickets
75 adult tickets
65 senior tickets
check:
(3)

(3)

(3)

(3)

OK