Can someone give me a thorough explanation of how to do this? it would a lot if you did it fast. (if it's thorough enough i will mark brainliest)

Hi there!
To write a equation of a graph, we must follow the formula y = mx + b, where m is the slope and b is the y-intercept. In this scenario, we can utilize this formula to get our answer. First, let's take a look at the y-intercept. To find this, we need to take a look at the graph. We can see that the line crosses the y-axis at the point (0,250). Hence, 250 will be our y-intercept. Now, we can move on to the slope. This can be found by first taking two points from our graph. Here are the two points I'll be using - (0,250)(2,200). Now, use the slope formula, which goes as m = y₂ - y₁ / x₂ - x₁. All we have to do is plug in the respective values from the coordinate points. We get - 

m = 200 - 250 / 2 - 0
m = -50 / 2
m = -25

Using the information we have derived, we can construct the equation y = -25x + 250. Usually, the answer should be written in standard form, which goes as Ax + By = C, where A, B, and C are numbers. Therefore, to derive y = -25x + 250 into standard format, we must add 25x to both sides. This gives us y + 25x = 250. Hope this helped and have a marvelous day!