Question

Pls help this is from khan academy

Answer 1

the desired equation is y = -3x + 7

Explanation:

The y-intercept can be read directly from the graph: (0, 7).

Another point on the graph is (2, 1).

As we move from (0, 7) to (2, 1), we see x (the run) increasing by 2 and y (the rise) decreasing by 6. Thus the slope of this line is m = rise/run = -6/2, or -3.

Start with the slope-intercept form of the equation of a straight line, which is y = mx + b.

Then 1 = (-3)(2) + b; find b:

1 = -6 + b, or b = 7

Then the desired equation is y = -3x + 7.

Answer 2

`y=-3x+7`

Explanation:

This is asking you to provide the equation is slope-intercept form:

`y=mx+b`

In this equation, m is the slope of the line and b is the y-intercept (where the x value is 0).

By looking at the graph, we can find the y-intercept:

`y-intercept=7\\\\m=7`

To find the slope of the line, you can count how many spaces it takes to go from one point to another. To do this, it's best to find an even point (1,4) and make your way to (0,7).

The slope is represented by
`(rise)/(run)` , where the rise is the change in the y-axis and the run is the change in the x-axis.

From (1,4) , move up (rise) as many spaces as it takes to get to the y-axis level of "7", which is 3 spaces. From here, move to the left (run) as many spaces as it takes to get to the x-axis level of "0", which is 1 space. Since you moved to the left, however, this means that the number will be a negative:

`(rise)/(run)=(3)/(-1)=-(3)/(1)=-3`

The slope is -3.

Insert the information into the equation:

`y=-3x+7`

:Done