Marcus bought a children's movie tickets for $6 each and an adult's movie tickets for $7 each. Write an algebraic expression for total amount Marcus spent.

Answer: 6N + 1 = M

Step-by-step explanation:

We simply Let C = the number of child tickets, Let A = the number of adult tickets, N = Number of ticket and M = total amount spend on ticket.

Therefore, the total number of ticket is C + A = N which is same as C = N-A ... (1)

And the total amount spent can be expressed as equal to 6C + 7A = M ... (2).

Now substitute (1) into (2).

We have 6 (N-A) + 7A = M

Which is 6N - 6A + 7A = M

That's equivalent to 6N + 1 = M.