Thanks to everyone who helped me with the previous questions
Last question:

y=3x+7 but I think it's y=-3x+7

y=-3x+7

Step-by-step explanation:

Rise/run

To find slope you can use the rise/run strategy. You count how many units up/down and then how many right/left. between each point on the line, it was down 3 units, right 1 unit (3/1) and since it was going down it would be negative.

As for the y-intercept, you look at where the line crosses the y-axis. In this case it was at (0,7), so the answer would be 7.

Plug your answers in and your equation should be y=-3+7.

You could also do y=7-3x, its the same equation but reversed, so you'll get the same line.

Hope this helps :)

in mathematics, a function is a relationship between two variables such that the value of one of the variables, called the dependent variable, is determined by the value of the other variable, called the independent variable. there is a specific term we use to describe the set of independent variables of a function.