The width of a rectangular room is 3 m shorter than its length. If its perimeter must not exceed
42 m, calculate the greatest length that the
room can have.
show work​

Step-by-step explanation:

First, let's convert this equation into slope-intercept form, which is represented by

where is the slope of the line and is the y-intercept.

With this, we know the slope of the line is and the y-intercept is .

Since we know the y-intercept is , we know the graph passes through the point , which eliminates options B and D.

Finally, since we know the slope is , we know the line is increasing, which eliminates option A, leaving us with option C.