It Does Not Matter Where You Put The Line, As The Slope Stays The Same. So, We Can Say That One Point Is (3,0)
(3,0) and (6,6)
So, The Slope Is 2.
The answer is c because if you do 7x60 you'll get 420 and 830-420=410 and 7x80 you'll get 560 and 970-560 is also 410.
you can work it out or put in random numbers until the two sides are equal