Homework Due Thursday, Feb 17

PART 1

Soft Copy

p. 148 5D 1 – 3; If you’re unsure of how to use the calculator , refer to the first chapter in the soft copy book (p. 31 graphing functions)

p. 150 6 – 10 (for no. 7, you will need to use a GDC) SEE DIRECTIONS BELOW

Read p. 156 and 157

p. 158 5H.1 1-4 (all parts)

p. 159 5H.2 1-5 (all parts)

Red Book

Ex. 4.2 1-8 all parts

DIRECTIONS FOR p. 150

For exercises 6-10, there are two statements given in each problem.  Write an equation for each statement and plot the two functions on the same graph (you can first graph on your GDC and then sketch the graph, or make a table and plot by hand).  Find the point of intersection of the two lines

For example,  No. 2 says:

Doubling a certain number and subtracting 5 gives the same result as subtracting 10 from the number then multiplying by 7.

Take “Doubling a certain number and subtracting 5” as the first statement and “subtracting 10 from the number then multiplying by 7” as the second statement. 

For the equation for the first statement, we’d let x represent “a certain number” so the equation  would be y = 2x – 5

For the second statement, our equation is y = (x – 10)*7 = 7x – 70

By graphing, we find that x = 13.  The number we’re looking for is 13.  

PART 2 **Updated**

p. 236 - 237

Read the pages and follow the examples.  Do the following sums in conjunction with these pages.

Buildings A and B begin with 540 litres of water in their tanks.  It takes building A 6 hours to use all its water and it takes building B 9 hours to use all its water.  Both buildings are losing water at constant rates (i.e. each hour, building A loses a certain amount of water and each hour, building B loses a different amount of water.)

1) Write an equation for the total consumption of water, y, after x hours for each building.  My equation should tell me for any number of hours that have passed how much water has been used.  See the plots shown on p. 236 and compare them with your equations.

2) Now write an equation for the amount of water in the tank, y, after x hours have passed for each building. 

Hint 1: each tank begins with 540 litres of water

Hint 2: use the rate of water loss (how many litres of water are lost each hour) to find the gradient of the equation

p. 238

Read Example 5.2.1b and then do the following problems:

1) For the pair of points A(1,2) and B(4, 4), plot the points and draw a line joining them.  Find the gradient of the line.  Now write an equation for the line (Hint: you have the gradient so all you need to write a full equation is the y-intercept).

2) For the pair of points A(1,4) and B(3,6), plot the points on the same graph as 1) and draw a line joining them.  Find the gradient and compare it to the gradient of the line in 1).  Now write an equation for the line.