Answer:
The rate of change at which the water level rise is 13/6 cm/minute.The slope of the line is 13/6.The value of y is 23, (12,23).
Explanation:
In the question the water rises 13 cm every 6minutes. Taking x to represent the time in minutes and y to represent the rise in cm then, find the rise y in time x as;
6 minutes=13 cm
1 minute=?---------------------perform cross multiplication
(1*13)/6=13/6
Hence in 1 minute, the rise is 13/6 cm
Thus in 12 minutes, the rise will be ;
12 * 13/6 = 2*13= 26 cm
(x,y) will be (12,26)
Finding the slope of the line using point (6,13) and (x,y)
The rate of change at which the water level rises equals the slope of the line.This is the justification.