Math Journal Response #2 and #3

Page 567, Question 7
The information given to me is y=2. I have to state the m and b. I knew m (slope) equals to 0 because I was only given the y intercept which means there is is no slope. Next I sketched the graph on the grid provided which was pretty easy. There was no x intercept. Then I had to draw a line with equation y=2x-4. After I did that I had to state the coordinates of the point of intersection of the two lines which was (3,2). And then I had to draw a line with equation y=-5.

When you look for the x intercept you set the y intercept to 0. Why is that?
That is because whenever we look at the y intercept the x intercept is always 0, so if want to find the x intercept we would set the y intercept to 0.

Page 605, Question 8
The information given to me is: After 7 days of heavy rainstorms, the water level in a river peaked at 2.85m above the regular level. Four days later the water dropped to 2.25m above the regular level. I had to determine a function h(t) which describes the height of the river above regular level as a function of time. The mistake I made while doing this was that I put the height of the river as X and the time as Y which gave me the wrong answer. But after I realized the mistake and corrected it I got the right answer which is -0.15t+2.85. -0.15 was the slope and it represented the rate at which the water level was dropping by meters per day.