To find the slope, we must put the equation in y = mx + b form, and m represents ur slope.
7x - 2y = 4....subtract 7x from both sides
-2y = -7x + 4 ...now divide both sides by -2
y = (-7/-2)x + (4/-2)
y = 7/2x - 2....now we have it in y = mx + b form, and since m is ur slope, ur slope in this equation is 7/2.
The most precise is 4.00 because that is equal to 10.16 cm and that is the most closes to an exact measurment.
The answer is b. x=77, y=63
The prisoners could do a pattern that could signal who has already been in the room. So for example, one light off, both lights off, one light on, both lights off. But with left and right lights to make the sequence last as long as possible. Then after that sequence to have the last one be the signal that everyone has been in there. I dunno this is tricky lol