The problem is actually already factored for you. They are asking you to just set the equation to zero. Find the zeros.
Answer:
He can buy up to 20 tickets (ie 20 tickets or less)
The equation is 10+3.25x+5 = 80
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Explanation:
10 = admission cost
3.25 = cost per ticket
x = number of tickets
3.25x = cost from buying x number of tickets
5 = cost of nachos & coke
10+3.25x+5 = total cost of admission, tickets, and food/drink
10+3.25x+5 = 80 since this is the amount he has in his pocket
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Let's solve for x
10+3.25x+5 = 80
3.25x+15 = 80
3.25x = 80-15 .... subtract 15 from both sides
3.25x = 65
x = 65/3.25 ........ divide both sides by 3.25
x = 20
Billy can buy up to 20 tickets (ie 20 tickets or less).
A. We are going to form 7 digit numbers from the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
where the first digit cannot be 0 or 1.
so we have 8 choices for the 1. digit, and 10 choices for all the other 6 digits.
this means there are

possible numbers.
b.
consider the numbers which start with 911. There are

such numbers, since for the 4th, 5th, 6th and 7th digits we have 10 choices.
then we remove this number, from the one we found in a:
There are in total

numbers which don't start with 911.
Answer:
a.

b.7,990,000
and you graph it from -4 to the right with close circle
Hope this help
I believe it’s just 61/100