Answer:
y = -x + 30
Explanation:
You will want to put the equation in the form y = mx + b where m is the slope and b is the y-intercept (an example is y = 2x - 1).
First, to find the slope you want to find how much x goes up by when y goes up by 1. You know from the table that when y goes up by 5, x goes up by -5 (using the points (10, 20) and (5, 25))
Then, you can divide each value by 5, so it would be when y goes up by 1, x goes up by -1. That means the slope is -1.
So far, the equation is y = -x + b. To find b, you can plug in one of the points you have and solve for b. For example, substitute in x = 10 and y = 20, so:
20 = -10 + b
add 10 to both sides
30 = b
So you know the equation is y = -x + 30
Please let me know if any parts of these explanation are confusing, I definitely think this concept can be confusing at time. Good luck with your work! :)