Let w be the width and l the length of the rectangle.
Then:

Solving the above system we get:

Therefore:

then

,which is the length,
And then the width
The answer is C because the numbers increase by 2 each time.
X= 4.167 you cross multiply both the equations. so you get 30x - 50x = 10x - 125. you shift all the values of x on side and then divide it by 125 sso you get x= 4.167
Substitute the input (x) numbers for x . Example: y= 5x substitute -3 for X
5 x -3 = -15. So there's your first answer for the first chart.