Math Journal #2 and #3

  1. For my unit 8 math journal, i did question 7 on page 567.The question gives us a starting function, as well as a blank cartesian plane. The question provides the student with a base point to start the question off with, before building on that as the question progresses.

when i first read the problem, i had to think about it. i new what my starting point was, but needed to figure out where to go from there. The formula y=mx+b was a key component in the problem, as well as knowing how to find the y-intercept and x-intercept.

Knowing what to do during the question was one thing, but realising how to apply it later was another. Part of the question asked for the domain and range of the equation, which made me think back to last unit where finding the domain and range was important. I remembered that if a ordered pair or equation has no x-intercept, it’s a zero slope, and the line runs across the graph horizontal without touching the x-axis

2) When you look for the x-intercept given a equation, you set y = 0 then solve for x. This is because where the point intercepts either the y or x axis, the other will be at zero on a graph. An x-intercept is a point on the graph where y is zero, and a y-intercept is a point on the graph where x is zero.

3) For my unit 9 math journal, i did question 8 on page 605. The question gives you a scenario where after 7 days of heavy rain, the water level of a river is 2.85m above regular level. After four more days, the water dropped to 2.25m above regular level. The questions asks that you create a function h(t) for the height of the river above regular level as a function of time, assuming t=0 at peak water level.

This question forced me to think a bit. Because there was so much information being given at once, I didn’t know where to start. When i figured it out, I knew the first thing i had to do was find the slope of the equation, and then plug it into the function.

I used the knowledge I already possessed from previous lessons to figure out how to do this question. I was on the right track, but i had to check the answer to figure out what my final answer should look like. The question confused me a bit, but overall I felt okay doing the question. I feel like if I hadn’t overthought the question, i would have been able to complete it without help.



Leave a Reply