Explain why you cannot use y = mx + b to find the equation of a vertical line.

because the slope would be 1/0 which is undefined

Step-by-step explanation:

Because a vertical line has an undefined slope. If you were to use rise over run you get any number over 0 (ex. 7/0). You cannot divide any number by zero which means you will get an undefined answer.

mr. graef told us it is 13 pints

step-by-step explanation:

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."