Let's call the event of the red die to show a six as event A, and the event of the green die to show a six as event B.
The theoretical probability is defined as the ratio of the number of favourable outcomes to the number of possible outcomes. On both dices, we have 6 possible outcomes(the numbers from 1 to 6), with one favourable outcome(the number 6), therefore, the probabilities of those events are:

Each roll is independent from each other, then, the probability of both events happening simultaneously is given by their product:

Using the additive rule of probability, we have the following equation for our problem:

the probability that the red die shows a six or the green die shows a six is 11/36.
You have a bucket 1 gallon big.
To mix cleaner and water you need to divide the bucket's capacity into 4.
It's easy in this case as gallon is divided into quarts (1 gallon = 4 quarts).
We know that one part will be cleaner, it means that you will need to use 1 quart of the cleaner.
Subtract 3x from both sides:
-6y = -3x + 6
divide both sides by -6 to get y by itself:
y = 1/2x - 1
function notation is rewriting y as a function:
f(x) = 1/2x -1
For the 1st one we need to solve x. x-y=2 step1: x-y+y=2+y answer: x=y+2