If you look up distributive property online, there will be really good videos to help you remember. Hope that will help you:)
The answer is B, I hope this helps! (don't forget to give brainliest)
In order to solve this you have to use the pythagorean’s theorem, which is a^2+b^2=c^2. from the problem you can find out you have a=13ft and c=24ft. c is your hypotenuse. you then solve and you get b=20.17ft. you can check to make sure the answer is right, but that is how you solve it. And the ladder would reach 20.17ft.
Given equation is y=3x+3 and 
Let's simplify the 2nd equation before we can start graph so that calculation will be easy
multiply both sides by 3 to cancel out fractions
y=3x+3
which is exactly same as the first equation so graph of both will be exactly same and solution will be infinitely many solutions.
y=3x+3 has y-intercept 3 so first point will be (0,3). Slope is 3 so rise 3 unit up then 1 right and graph the new point.
