Please, post just one problem at a time, or (if you post more than one), indicate which one you want to focus on first. Even more important, please do whatever you can to get started on each problem; I'm sure you know at least some basics.
What does "intersecting" mean? Look it up if you're not sure.
Then what would "two intersecting lines" look like? Draw the graph, or at least explain in words what the graph would look like.
Bob's car rental company makes you pay 10 dollars per day you rent the car and a 30 dollar insurance fee
joe's car rental company makes you pay 30 dollars per day you rent the car and a 10 dollar insurance fee
how many days do you need to rent a car for the cost for renting both are the same
bob=10x+30
joe=30x+10
set each to each other
10x+30=30x+10
subtract 10x
30=20x+10
subtract 10
20=20x
divide both sides by 20
1=x
you need to rent 1 day for them to be equal
Normally when there is similar terms and when you have to figure out if it is factorable or prime you must first begin factoring it and if it does not work it is prime.
Hope this helps, ask me if you have any questions.
3.3 x 5 = 16.5 cm
Happy to Help!